Add GitHub Actions workflow to check for changelog entry (#47)

* Add GitHub Actions workflow to check for changelog entry
* Update CHANGELOG.md

Author: dermatz

.github/workflows/check-changelog.yml

@@ -0,0 +1,29 @@
+name: Check for CHANGELOG.md Update
+
+permissions:
+    contents: read
+
+on: [pull_request]
+
+jobs:
+    check-changelog:
+        runs-on: ubuntu-latest
+        steps:
+            - name: Check out the repository
+              uses: actions/checkout@v3
+
+            - name: Get the list of modified files
+              id: changed-files
+              run: |
+                  git fetch origin ${{ github.base_ref }} --depth=1
+                  git diff --name-only origin/${{ github.base_ref }} ${{ github.sha }} > changed_files.txt
+                  cat changed_files.txt
+
+            - name: Check if CHANGELOG.md was updated
+              run: |
+                  if ! grep -q "^CHANGELOG.md$" changed_files.txt; then
+                    echo "::error::CHANGELOG.md was not updated!"
+                    exit 1
+                  else
+                    echo "CHANGELOG.md has been updated."
+                  fi

CHANGELOG.md

@@ -8,6 +8,7 @@ All notable changes to this project will be documented in this file.
 
 -   added documentation for color assignments in `CONTRIBUTING.md` to standardize the use of color variables in bash scripts
 -   added detailed color definitions and a usage example in the new "Color Assignments" section
+-   added Github Action to check if Pull Request contains `CHANGELOG.md` updates
 
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