Add merge-dependabot-pr.yml workflow

* Fix `mail-supplier` to use `angus-mail.version` project property

.github/workflows/merge-dependabot-pr.yml

@@ -0,0 +1,14 @@
+name: Merge Dependabot PR
+
+on:
+  pull_request:
+    branches:
+      - main
+
+run-name: Merge Dependabot PR ${{ github.ref_name }}
+
+jobs:
+  merge-dependabot-pr:
+    permissions: write-all
+
+    uses: spring-io/spring-github-workflows/.github/workflows/spring-merge-dependabot-pr.yml@v1

supplier/mail-supplier/build.gradle

@@ -5,7 +5,7 @@ ext {
 dependencies {
     api 'org.springframework.integration:spring-integration-mail'
     api 'org.springframework.boot:spring-boot-starter-mail'
-    api 'org.eclipse.angus:jakarta.mail:2.0.2'
+    api "org.eclipse.angus:jakarta.mail:${property('angus-mail.version')}"
 
     testImplementation "com.icegreen:greenmail:$greenmailVersion"
 }