Bump com.github.johnrengelman.shadow from 6.1.0 to 7.1.2

Bumps com.github.johnrengelman.shadow from 6.1.0 to 7.1.2.

---
updated-dependencies:
- dependency-name: com.github.johnrengelman.shadow
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

agent/build.gradle

@@ -1,5 +1,5 @@
 plugins {
-    id 'com.github.johnrengelman.shadow' version '6.1.0'
+    id 'com.github.johnrengelman.shadow' version '7.1.2'
     id "java"
     id "maven-publish"
     id "signing"