chore(deps): update github-actions (major)

[mend-for-github-com]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	major	v3 -> v4
docker/login-action	action	major	v2 -> v3
magefile/mage-action	action	major	v2 -> v3
magnetikonline/action-golang-cache	action	major	v3 -> v4

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Release Notes

actions/checkout (actions/checkout)

v4

Compare Source

• Add support for partial checkout filters

docker/login-action (docker/login-action)

v3

Compare Source

magefile/mage-action (magefile/mage-action)

v3

Compare Source

magnetikonline/action-golang-cache (magnetikonline/action-golang-cache)

v4

Compare Source

• Provide action outputs of build-cache-path, module-cache-path and cache-key.
• Bump actions/setup-go@v4
• Some README.md cleanups.

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