Kapt: Move line metadata to .kaptMetadata external files (KT-22386)

Placing location table inside .java file triggers annotation processor to run on each line table modification (even when the stub declarations themselves are the same). So we move it to the separate file.

plugins/kapt3/kapt3-compiler/testData/converter/errorLocationMapping.txt

@@ -1,7 +1,3 @@
-/**
- * @KaptMetadata
- */
-
 import kotlin.reflect.KClass;
 
 @kotlin.Metadata()
@@ -13,9 +9,6 @@ public abstract @interface Anno {
 
 ////////////////////
 
-/**
- * @KaptMetadata
- */
 
 import kotlin.reflect.KClass;
 
@@ -30,9 +23,6 @@ public final class ErrorInAnnotation {
 
 ////////////////////
 
-/**
- * @KaptMetadata
- */
 
 import kotlin.reflect.KClass;
 
@@ -70,9 +60,6 @@ public final class ErrorInConstructorParameter {
 
 ////////////////////
 
-/**
- * @KaptMetadata
- */
 
 import kotlin.reflect.KClass;
 
@@ -143,9 +130,6 @@ public final class ErrorInDeclarations {
 
 ////////////////////
 
-/**
- * @KaptMetadata
- */
 
 import kotlin.reflect.KClass;
 
@@ -159,9 +143,6 @@ public final class ErrorInSupertype {
 
 ////////////////////
 
-/**
- * @KaptMetadata
- */
 
 import kotlin.reflect.KClass;