Use pyproject.toml as Python version source

.gitattributes

@@ -0,0 +1,4 @@
+# See: https://git-scm.com/docs/gitattributes
+
+# Disable Git converting line endings in files (i.e., core.autocrlf=true).
+* -text

.github/workflows/check-mkdocs-task.yml

@@ -4,8 +4,6 @@ name: Check Website
 env:
   # See: https://github.com/actions/setup-go/tree/main#supported-version-syntax
   GO_VERSION: "1.17"
-  # See: https://github.com/actions/setup-python/tree/main#available-versions-of-python
-  PYTHON_VERSION: "3.9"
 
 # See: https://docs.github.com/actions/writing-workflows/choosing-when-your-workflow-runs/events-that-trigger-workflows
 on:
@@ -88,7 +86,7 @@ jobs:
       - name: Install Python
         uses: actions/setup-python@v5
         with:
-          python-version: ${{ env.PYTHON_VERSION }}
+          python-version-file: pyproject.toml
 
       - name: Install Poetry
         run: pip install poetry

.github/workflows/check-python-task.yml

@@ -1,10 +1,6 @@
 # Source: https://github.com/arduino/tooling-project-assets/blob/main/workflow-templates/check-python-task.md
 name: Check Python
 
-env:
-  # See: https://github.com/actions/setup-python/tree/main#available-versions-of-python
-  PYTHON_VERSION: "3.9"
-
 # See: https://docs.github.com/actions/writing-workflows/choosing-when-your-workflow-runs/events-that-trigger-workflows
 on:
   create:
@@ -73,7 +69,7 @@ jobs:
       - name: Install Python
         uses: actions/setup-python@v5
         with:
-          python-version: ${{ env.PYTHON_VERSION }}
+          python-version-file: pyproject.toml
 
       - name: Install Poetry
         run: pip install poetry
@@ -104,7 +100,7 @@ jobs:
       - name: Install Python
         uses: actions/setup-python@v5
         with:
-          python-version: ${{ env.PYTHON_VERSION }}
+          python-version-file: pyproject.toml
 
       - name: Install Poetry
         run: pip install poetry

.github/workflows/deploy-cobra-mkdocs-versioned-poetry.yml

@@ -4,8 +4,6 @@ name: Deploy Website
 env:
   # See: https://github.com/actions/setup-go/tree/main#supported-version-syntax
   GO_VERSION: "1.17"
-  # See: https://github.com/actions/setup-python/tree/main#available-versions-of-python
-  PYTHON_VERSION: "3.9"
 
 on:
   push:
@@ -76,7 +74,7 @@ jobs:
       - name: Install Python
         uses: actions/setup-python@v5
         with:
-          python-version: ${{ env.PYTHON_VERSION }}
+          python-version-file: pyproject.toml
 
       - name: Install Poetry
         run: |

.github/workflows/spell-check-task.yml

@@ -1,10 +1,6 @@
 # Source: https://github.com/arduino/tooling-project-assets/blob/main/workflow-templates/spell-check-task.md
 name: Spell Check
 
-env:
-  # See: https://github.com/actions/setup-python/tree/main#available-versions-of-python
-  PYTHON_VERSION: "3.9"
-
 # See: https://docs.github.com/actions/writing-workflows/choosing-when-your-workflow-runs/events-that-trigger-workflows
 on:
   create:
@@ -55,7 +51,7 @@ jobs:
       - name: Install Python
         uses: actions/setup-python@v5
         with:
-          python-version: ${{ env.PYTHON_VERSION }}
+          python-version-file: pyproject.toml
 
       - name: Install Poetry
         run: pip install poetry

.github/workflows/test-go-integration-task.yml

@@ -4,8 +4,6 @@ name: Test Integration
 env:
   # See: https://github.com/actions/setup-go/tree/main#supported-version-syntax
   GO_VERSION: "1.17"
-  # See: https://github.com/actions/setup-python/tree/main#available-versions-of-python
-  PYTHON_VERSION: "3.9"
 
 # See: https://docs.github.com/actions/writing-workflows/choosing-when-your-workflow-runs/events-that-trigger-workflows
 on:
@@ -88,7 +86,7 @@ jobs:
       - name: Install Python
         uses: actions/setup-python@v5
         with:
-          python-version: ${{ env.PYTHON_VERSION }}
+          python-version-file: pyproject.toml
 
       - name: Install Poetry
         run: pip install poetry