Have Renovate auto-update proto version (#160)

Author: trask

.github/renovate.json5

@@ -22,5 +22,18 @@
       ],
       enabled: false,
     },
-  ]
+  ],
+  customManagers: [
+    {
+      customType: 'regex',
+      datasourceTemplate: 'github-releases',
+      managerFilePatterns: [
+        'build.gradle.kts',
+      ],
+      matchStrings: [
+        '"(?<currentValue>.+?)" // renovate\\(github-releases\\): (?<depName>[^\\s]+)',
+      ],
+      versioningTemplate: 'semver',
+    },
+  ],
 }

build.gradle.kts

@@ -16,7 +16,7 @@ val snapshot = true
 // end
 
 // The release version of opentelemetry-proto used to generate classes
-var protoVersion = "1.9.0"
+var protoVersion = "1.9.0" // renovate(github-releases): open-telemetry/opentelemetry-proto
 
 // Compute the artifact version, include the "-SNAPSHOT" suffix if not releasing
 // Release example: 1.5.0