Skip plugins block in UsePropertyAssignmentSyntax (#7337)

* Skip plugins block in UsePropertyAssignmentSyntax

The recipe was incorrectly converting `version '3.19'` inside
`plugins { }` blocks to `.version = '3.19'`. In the Gradle plugins
DSL, `version` is part of the plugin declaration syntax, not a
property assignment. Walk the cursor tree to detect and skip
method invocations inside plugins blocks.

* Skip plugins block by not recursing into it

Instead of checking cursor ancestry on each match, skip
the super.visitMethodInvocation call for plugins blocks
so their children are never visited.

Author: timtebeek

rewrite-gradle/src/main/java/org/openrewrite/gradle/UsePropertyAssignmentSyntax.java

@@ -54,6 +54,10 @@ public TreeVisitor<?, ExecutionContext> getVisitor() {
         return Preconditions.check(new FindSourceFiles("**/*.gradle"), new JavaVisitor<ExecutionContext>() {
             @Override
             public J visitMethodInvocation(J.MethodInvocation method, ExecutionContext ctx) {
+                if ("plugins".equals(method.getSimpleName())) {
+                    return method;
+                }
+
                 J.MethodInvocation m = (J.MethodInvocation) super.visitMethodInvocation(method, ctx);
 
                 if (m.getArguments().size() != 1 || m.getArguments().get(0) instanceof J.Empty) {

rewrite-gradle/src/test/java/org/openrewrite/gradle/UsePropertyAssignmentSyntaxTest.java

@@ -22,6 +22,7 @@
 
 import static org.openrewrite.gradle.Assertions.buildGradle;
 import static org.openrewrite.gradle.Assertions.buildGradleKts;
+import static org.openrewrite.gradle.Assertions.settingsGradle;
 
 class UsePropertyAssignmentSyntaxTest implements RewriteTest {
 
@@ -170,6 +171,49 @@ void kotlinDslMethodCallUnchanged() {
         );
     }
 
+    @Test
+    void pluginVersionUnchangedInPluginsBlock() {
+        rewriteRun(
+          spec -> spec.recipe(new UsePropertyAssignmentSyntax("version")),
+          settingsGradle(
+            """
+              plugins {
+                  id 'com.gradle.develocity' version '3.19'
+              }
+              """
+          )
+        );
+    }
+
+    @Test
+    void pluginVersionUnchangedInBuildGradlePluginsBlock() {
+        rewriteRun(
+          spec -> spec.recipe(new UsePropertyAssignmentSyntax("version")),
+          buildGradle(
+            """
+              plugins {
+                  id 'com.example.plugin' version '1.0'
+              }
+              """
+          )
+        );
+    }
+
+    @Test
+    void versionOutsidePluginsBlockConverted() {
+        rewriteRun(
+          spec -> spec.recipe(new UsePropertyAssignmentSyntax("version")),
+          buildGradle(
+            """
+              version '1.0-SNAPSHOT'
+              """,
+            """
+              version = '1.0-SNAPSHOT'
+              """
+          )
+        );
+    }
+
     @Test
     void noArgMethodCallUnchanged() {
         rewriteRun(