java 18 is generally available

GitOrigin-RevId: 6da5af5f9d23adf4aacfc5752765103bb6732a8a

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/javaDoc/EmptySnippet.java

@@ -1,6 +1,6 @@
 /**
  * A simple program.
- * {<warning descr="'@snippet' tag is not available at this language level">@snippet</warning> :}
+ * {@snippet :}
  */
 class A {
 }

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/javaDoc/OnlyEmptyLinesInSnippet.java

@@ -1,6 +1,6 @@
 /**
  * A simple program.
- * {<warning descr="'@snippet' tag is not available at this language level">@snippet</warning> :
+ * {@snippet :
  *
  * }
  */

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/javaDoc/Snippet.java

@@ -1,4 +1,4 @@
-/** {<warning descr="'@snippet' tag is not available at this language level">@snippet</warning> :
+/** {@snippet :
  *  Body
  * }
  */

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/javaDoc/SnippetInlineTag.java

@@ -1,5 +1,5 @@
 /**
- * {<warning descr="'@snippet' tag is not available at this language level">@snippet</warning> lang=JAVA :
+ * {@snippet lang=JAVA :
  *   public class ShowOptional {
  *     void show(Optional<String> v) {
  *         // @start region="example"

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/javaDoc/SnippetInstructions.java

@@ -1,4 +1,4 @@
-/** {<warning descr="'@snippet' tag is not available at this language level">@snippet</warning> :
+/** {@snippet :
  *   Optional<Integer> v = null;
  *   if (v.isPresent()) {
  *      System.out.println("v: " + v.get());

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/javaDoc/SnippetInstructionsWithUnhandledThrowable.java

@@ -1,4 +1,4 @@
-/** {<warning descr="'@snippet' tag is not available at this language level">@snippet</warning> :
+/** {@snippet :
  * FileInputStream is = new FileInputStream("hello.world");
  * int r = is.read();
  * }

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/javaDoc/SnippetMethod.java

@@ -1,4 +1,4 @@
-/** {<warning descr="'@snippet' tag is not available at this language level">@snippet</warning> :
+/** {@snippet :
  * void f() {}
  * }
  */

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/javaDoc/UnalignedLeadingAsterisks.java

@@ -2,7 +2,7 @@ class A {
 
       /**
      * A simple program.
-     * {<warning descr="'@snippet' tag is not available at this language level">@snippet</warning>  :
+     * {@snippet  :
      * class  HelloWorld {
  *     void
   *       f(