Bump com.google.cloud.tools:appengine-maven-plugin from 2.7.0 to 2.8.0

Bumps [com.google.cloud.tools:appengine-maven-plugin](https://github.com/GoogleCloudPlatform/appengine-plugins) from 2.7.0 to 2.8.0.
- [Release notes](https://github.com/GoogleCloudPlatform/appengine-plugins/releases)
- [Changelog](https://github.com/GoogleCloudPlatform/appengine-plugins/blob/main/CHANGELOG.md)
- [Commits](GoogleCloudPlatform/appengine-plugins@v2.7.0...v2.8.0)

---
updated-dependencies:
- dependency-name: com.google.cloud.tools:appengine-maven-plugin
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

pom.xml

@@ -196,7 +196,7 @@
 			<plugin>
 				<groupId>com.google.cloud.tools</groupId>
 				<artifactId>appengine-maven-plugin</artifactId>
-				<version>2.7.0</version>
+				<version>2.8.0</version>
 				<configuration>
 					<projectId>${appengine.app.name}</projectId>
 					<version>${appengine.app.version}</version>