feat: remove the deprecated .cspell.json dict

[xmfcx]

Description

We have .cspell and a deprecated cspell/.cspell file within the repository.

Almost every repository within the autoware folder is referring to the .cspell (for now from tier4 org):

mfc@whale:~/projects/autoware$ grep -r "main/.cspell.json" .
./src/vehicle/external/pacmod_interface/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/vehicle/awsim_labs_vehicle_launch/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/vehicle/sample_vehicle_launch/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/launcher/autoware_launch/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/sensor_component/external/sensor_component_description/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/sensor_component/external/nebula/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/core/autoware_lanelet2_extension/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/core/autoware_utils/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/core/autoware_internal_msgs/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/core/autoware_adapi_msgs/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/core/autoware_common/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/core/autoware_cmake/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/core/autoware.core/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/core/autoware_msgs/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/param/autoware_individual_params/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/sensor_kit/sample_sensor_kit_launch/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/sensor_kit/external/awsim_sensor_kit_launch/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/sensor_kit/awsim_labs_sensor_kit_launch/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/universe/external/tier4_autoware_msgs/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/universe/external/tier4_ad_api_adaptor/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/universe/autoware.universe/.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/universe/autoware.universe/.github/workflows/spell-check-daily.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/tools/.github/workflows/spell-check-all.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./src/tools/.github/workflows/spell-check-partial.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json
./.github/workflows/spell-check-differential.yaml:          cspell-json-url: https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/.cspell.json

The only exception:

mfc@whale:~/projects/autoware$ grep -r "cspell/.cspell.json" src/
src/universe/external/pointcloud_to_laserscan/.github/workflows/spell_check_pr.yml:            https://raw.githubusercontent.com/tier4/autoware-spell-check-dict/main/cspell/.cspell.json

This PR removes the deprecated file and the CI check that attempts to prevent changes to the deprecated file.

Related links

None.

Notes for reviewers

None.

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[xmfcx]

Ready for review ✅