Start using Java > 11 language features in Error Prone tests

This is a first step towards raising the minimum supported JDK version Error
Prone to JDK 17.

PiperOrigin-RevId: 673432814

Author: cushon

check_api/pom.xml

@@ -168,7 +168,7 @@
             <id>default-compile</id>
             <configuration>
               <jdkToolchain>
-                <version>11</version>
+                <version>17</version>
               </jdkToolchain>
             </configuration>
           </execution>

core/src/test/java/com/google/errorprone/bugpatterns/FinallyTest.java

@@ -55,15 +55,20 @@ public void lambda() {
     compilationHelper
         .addSourceLines(
             "Test.java",
-            "class Test {",
-            "  void f() {",
-            "    try {",
-            "    } catch (Throwable t) {",
-            "  } finally {",
-            "      Runnable r = () -> { return; };",
-            "    }",
-            "  }",
-            "}")
+            """
+            class Test {
+              void f() {
+                try {
+                } catch (Throwable t) {
+                } finally {
+                  Runnable r =
+                      () -> {
+                        return;
+                      };
+                }
+              }
+            }
+            """)
         .doTest();
   }
 }

pom.xml

@@ -182,8 +182,8 @@
         <artifactId>maven-compiler-plugin</artifactId>
         <version>3.13.0</version>
         <configuration>
-          <source>11</source>
-          <target>11</target>
+          <source>17</source>
+          <target>17</target>
           <parameters />
           <compilerArgs>
             <arg>--add-exports=java.base/jdk.internal.javac=ALL-UNNAMED</arg>
@@ -284,7 +284,7 @@
         <configuration>
           <toolchains>
             <jdk>
-              <version>11</version>
+              <version>17</version>
               <version>24</version>
             </jdk>
           </toolchains>