gradle: configure updateScript per major version

Previously the regex for updating Gradle matched any major version,
resulting in version bumps like #504857 where gradle_8 was updated to
9.4.1.
After this change, the version regexp is tagged to a specific major
version. That way gradle_8 is only updated to versions that start with
'8'. At the same time version updates are enabled for gradle_9 if they
start with '9'.
Last but not least, `nix-update-script` is now called with
`--use-github-releases` because without it the updater defaults to using
GitHub's releases Atom feed, and just returns the most recent releases,
causing the gradle_8 update to fail because no matching release version
could be found.

pkgs/development/tools/build-managers/gradle/default.nix

@@ -119,7 +119,7 @@ let
 
       # Put the update script in passthru. Should only be on a single attrpath
       # so that nixpkgs-update doesn't create duplicate PRs.
-      enableUpdateScript ? false,
+      updateScriptMajorVersion ? null,
     }@genArgs:
 
     {
@@ -305,14 +305,15 @@ let
         gradle-unwrapped = mkGradle genArgs;
       };
       passthru.updateScript =
-        if enableUpdateScript then
+        if updateScriptMajorVersion != null then
           nix-update-script {
             extraArgs = [
               "--url=https://github.com/gradle/gradle"
+              "--use-github-releases"
               # Gradle’s .0 releases are tagged as `vX.Y.0`, but the actual
               # release version omits the `.0`, so we’ll wanto to only capture
               # the version up but not including the the trailing `.0`.
-              "--version-regex=^v(\\d+\\.\\d+(?:\\.[1-9]\\d?)?)(\\.0)?$"
+              "--version-regex=^v(${updateScriptMajorVersion}\\.\\d+(?:\\.[1-9]\\d?)?)(\\.0)?$"
             ];
           }
         else
@@ -367,13 +368,13 @@ rec {
     version = "9.4.0";
     hash = "sha256-YOpyM1bYEmPoAC/sD8+eKw7uDAhQx6PXqwpj8szGAfM=";
     defaultJava = jdk21;
+    updateScriptMajorVersion = "9";
   };
   gradle_8 = mkGradle {
     version = "8.14.4";
     hash = "sha256-8XcSmKcPbbWina9iN4xOGKF/wzybprFDYuDN9AYQOA0=";
     defaultJava = jdk21;
-    # Only enable this on *one* version to avoid duplicate PRs.
-    enableUpdateScript = true;
+    updateScriptMajorVersion = "8";
   };
   gradle_7 = mkGradle {
     version = "7.6.6";