Add checkout step to Maven and publish workflows

Ensure the source code is checked out before setting up Java in both workflows. This prevents potential errors caused by missing source files during the build and publish processes.

Author: NonSwag

.github/workflows/maven-publish.yml

@@ -9,6 +9,8 @@ jobs:
       REPOSITORY_TOKEN: ${{ secrets.REPOSITORY_TOKEN }}
     runs-on: ubuntu-latest
     steps:
+      - name: Checkout sources
+        uses: actions/checkout@v4
       - name: Setup Java
         uses: actions/setup-java@v4
         with:

.github/workflows/publish.yml

@@ -8,6 +8,8 @@ jobs:
       HANGAR_API_TOKEN: ${{ secrets.HANGAR_API_TOKEN }}
     runs-on: ubuntu-latest
     steps:
+      - name: Checkout sources
+        uses: actions/checkout@v4
       - name: Setup Java
         uses: actions/setup-java@v4
         with: