Update pattern for finding diagnostics in diagnostic tests

Also use updated diagnostic pattern in TreesCompareTest.
In rare cases diagnostic was cut too early on !> characters,
that were a part of diagnostic parameter:
<!DIAGNOSTIC("Type<DefinitelyNotNullTypeArgument!!>")!>

compiler/tests-common/tests/org/jetbrains/kotlin/checkers/BaseDiagnosticsTest.kt

@@ -406,6 +406,8 @@ abstract class BaseDiagnosticsTest : KotlinMultiFileTestWithJava<TestModule, Tes
 
         val RENDER_DIAGNOSTICS_MESSAGES = "RENDER_DIAGNOSTICS_MESSAGES"
 
+        val DIAGNOSTIC_IN_TESTDATA_PATTERN = Regex("<!>|<!(.*?(\\(\".*?\"\\)|\\(\\))??)+(?<!<)!>")
+
         fun parseDiagnosticFilterDirective(
             directiveMap: Map<String, String>,
             allowUnderscoreUsage: Boolean
@@ -477,8 +479,6 @@ abstract class BaseDiagnosticsTest : KotlinMultiFileTestWithJava<TestModule, Tes
             )
         }
 
-        private val DIAGNOSTIC_IN_TESTDATA_PATTERN = Regex("(<!>|(<!(.(\".*\")*?)+?!>))")
-
         fun loadTestDataWithoutDiagnostics(file: File): String {
             val textWithoutDiagnostics = KotlinTestUtils.doLoadFile(file).replace(DIAGNOSTIC_IN_TESTDATA_PATTERN, "")
             return StringUtil.convertLineSeparators(textWithoutDiagnostics.trim()).trimTrailingWhitespacesAndAddNewlineAtEOF()