feat: extract from edx-platform

This contribution is part of the [FC-0012 project](https://openedx.atlassian.net/l/cp/XGS0iCcQ) which is sparked by the [Translation Infrastructure update OEP-58](https://open-edx-proposals.readthedocs.io/en/latest/architectural-decisions/oep-0058-arch-translations-management.html#specification).

.github/workflows/extract-translation-source-files.yml

@@ -79,6 +79,7 @@ jobs:
             python_module_name: sql_grader
           - repo_name: xblock-submit-and-compare
             python_module_name: submit_and_compare
+          - repo_name: edx-platform
 
     runs-on: ubuntu-latest
     continue-on-error: true
@@ -102,15 +103,40 @@ jobs:
           repository: openedx/${{ matrix.repo.repo_name }}
           path: translations/${{ matrix.repo.repo_name }}
 
-      # Sets up Python
+
+      - name: prepare the environment with edx-platform specific changes
+        if: matrix.repo.repo_name == 'edx-platform'
+        run: |
+          # This is needed for edx-platform base.txt packages
+          sudo apt install -y libxml2-dev libxmlsec1-dev libxslt1-dev
+
+          # Remove unwanted `en` django/djangojs po files
+          rm -rf translations/${{ matrix.repo.repo_name }}/conf/locale/en
+          mkdir -p translations/${{ matrix.repo.repo_name }}/conf/locale/en/LC_MESSAGES
+
+      # Setup Python
       - name: setup python
         uses: actions/setup-python@v4
+        id: setup_python
         with:
           python-version: '3.8'
+          cache: pip
+          # Using wild-card for `edx-platf*rm` -> `edx-platform` which separates its dependencies from other repos
+          cache-dependency-path: |
+            requirements/translations.txt
+            translations/edx-platf*rm/requirements/edx/base.txt
 
       # Installs Python requirements from translations.txt
       - name: install requirements
-        run: pip install -r requirements/translations.txt
+        run: |
+          # Install requirements for all packages
+          pip install -r requirements/translations.txt
+
+          EDX_BASE_REQS=translations/edx-platform/requirements/edx/base.txt
+          if test -f $EDX_BASE_REQS; then
+            # Install edx-platform specific apps (e.g. wiki) which is required to extrat translations from
+            pip install -r $EDX_BASE_REQS
+          fi
 
       # Extracts the translation source files
       - name: extract translation source files
@@ -135,7 +161,8 @@ jobs:
           cd translations/${{ matrix.repo.repo_name }}
           # finds the directory containing the english locale usually located in
           # */*/conf/locale/en
-          EN_DIR=$(find . -type d -regex ".+conf\/locale\/en$")
+          EN_DIR=$(find . -type d -regex ".+conf\/locale\/en$" | head -n 1)
+          echo "EN_DIR=$EN_DIR" >> $GITHUB_ENV
           # If the directory is not found, exit with an error. This can happen if we add a repository that doesn't
           # comply with OEP-58, or it still doesn't have any translations yet
           if [ -z "$EN_DIR" ]; then
@@ -145,15 +172,31 @@ jobs:
           fi
           # remove translations/${{ matrix.repo.repo_name }}/.git so we don't commit a submodule
           rm -rf .git
+
+      # All repositories except for edx-platform follows the standard Django i18n pattern
+      - name: add repo translation source files openedx-translations
+        if: matrix.repo.repo_name != 'edx-platform'
+        run: |
           # finds the django.po and djangojs.po files generated by make
           # extract_translations into EN_DIR and adds them
+          cd translations/${{ matrix.repo.repo_name }}
           DJANGO_PATH=$(find $EN_DIR -name 'django.po')
           DJANGOJS_PATH=$(find $EN_DIR -name 'djangojs.po')
           # use (-f) to force add the files even if they are ignored in the source repo
           git add $DJANGO_PATH $DJANGOJS_PATH -f -v
           # Check the git statuses of the translation source files
           echo "GIT_STATUS=$(git status $DJANGO_PATH $DJANGOJS_PATH -s | wc -l)" >> $GITHUB_ENV
 
+      # edx-platform has multiple i18n files
+      - name: add edx-platform translation source files openedx-translations
+        if: matrix.repo.repo_name == 'edx-platform'
+        run: |
+          cd translations/${{ matrix.repo.repo_name }}
+          git add -f -v conf/locale/en/LC_MESSAGES/*.po
+          # Check the git statuses of the translation source files
+          echo "GIT_STATUS=$(git status conf/locale/en -s | wc -l)" >> $GITHUB_ENV
+
+      # This applies for all repositories that are _installable_ inside edx-platform
       - name: create plugin/xblock link
         if: ${{ matrix.repo.python_module_name }}
         run: |