Make CanonicalAnnotationSyntax an error

An annotation attribute with one value no longer has braces around it
(@State's storages), and an array of them no trailing comma
(SpotlessExcludesTest's @valuesource, which then fits on one line).

Author: abashev

buildSrc/src/main/groovy/open-java-format.error-prone-conventions.gradle

@@ -25,6 +25,7 @@ tasks.withType(JavaCompile).configureEach {
         nullaway {
             handleTestAssertionLibraries = true
         }
+        error('CanonicalAnnotationSyntax')
         error('FormatStringConcatenation')
         error('JUnitClassModifiers')
         error('JUnitMethodDeclaration')

gradle-open-java-format/src/test/java/com/palantir/javaformat/gradle/SpotlessExcludesTest.java

@@ -93,11 +93,7 @@ void format_ignores_excluded_directories(String srcDir) {
     }
 
     @ParameterizedTest
-    @ValueSource(
-            strings = {
-                "foo/generated_foo/src/bar",
-                "src/main/java/test/generatedNamespace",
-            })
+    @ValueSource(strings = {"foo/generated_foo/src/bar", "src/main/java/test/generatedNamespace"})
     void format_checks_non_generated_files(String srcDir) {
         project.buildGradle("""
             sourceSets {

open-java-format-idea-plugin/src/main/java/com/palantir/javaformat/intellij/PalantirJavaFormatSettings.java

@@ -37,9 +37,7 @@
 
 import static java.util.Optional.ofNullable;
 
-@State(
-        name = "PalantirJavaFormatSettings",
-        storages = {@Storage("open-java-format.xml")})
+@State(name = "PalantirJavaFormatSettings", storages = @Storage("open-java-format.xml"))
 public class PalantirJavaFormatSettings implements PersistentStateComponent<PalantirJavaFormatSettings.StoredSettings> {
 
     private StoredSettings state = new StoredSettings();