add gitflow actions for PR and snapshots (#64)

.github/workflows/add-to-platform-project.yml

@@ -0,0 +1,16 @@
+name: Add new issues to Platform project
+
+on:
+  issues:
+    types:
+      - opened
+
+jobs:
+  add-to-project:
+    name: Add issue to project
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/add-to-project@v0.4.0
+        with:
+          project-url: https://github.com/orgs/alphora/projects/3
+          github-token: ${{ secrets.ADD_TO_PLATFORM_PAT }}

.github/workflows/check-pr.yaml

@@ -0,0 +1,14 @@
+name: Check PR
+on: pull_request
+
+jobs:
+  maven:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-java@v3
+        with:
+          distribution: temurin
+          java-version: 11
+      - name: Run Checks
+        run: mvn --batch-mode --no-transfer-progress --update-snapshots verify

.github/workflows/publish-snapshot.yml

@@ -0,0 +1,23 @@
+name: Publish Snapshot
+on:
+  push:
+    branches:
+      - master
+
+jobs:
+  maven:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-java@v3
+        with:
+          distribution: temurin
+          java-version: 11
+          server-id: ossrh
+          server-username: MAVEN_USERNAME
+          server-password: MAVEN_PASSWORD
+      - name: Publish snapshot
+        run: mvn --batch-mode -no-transfer-progress --update-snapshots deploy
+        env:
+          MAVEN_USERNAME: ${{ vars.OSSRH_USERNAME }}
+          MAVEN_PASSWORD: ${{ secrets.OSSRH_TOKEN }}