Add BEAST.base dependency to version.xml and CI workflow

Add <depends on='BEAST.base' atleast='2.8.0'/> to version.xml for
consistency with other BEAST3 packages. Add GitHub Actions workflow
for running tests on push/PR.

Author: alexeid

.github/workflows/main.yml

@@ -0,0 +1,18 @@
+name: Unit/integration tests
+on: [ push, pull_request, workflow_dispatch ]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: 25
+          server-id: github
+          server-username: GITHUB_ACTOR
+          server-password: GITHUB_TOKEN
+      - run: mvn test
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

version.xml

@@ -1,4 +1,5 @@
 <package name='MM' version='1.3.0'>
+    <depends on='BEAST.base' atleast='2.8.0'/>
 
     <service type="beast.base.core.BEASTInterface">
         <provider classname="morphmodels.app.beauti.BeautiMorphModelAlignmentProvider"/>