[TD] Update diagnostics test data due to new test runners

Update includes:
- Changing syntax of `OI/`NI` tags from `<!NI;TAG!>` to `<!TAG{NI}!>`
- Fix some incorrect directives
- Change order of diagnostics in some places
- Remove ignored diagnostics from FIR test data (previously `DIAGNOSTICS` didn't work)
- Update FIR dumps in some places and add `FIR_IDENTICAL` if needed
- Replace all JAVAC_SKIP with SKIP_JAVAC directive

compiler/testData/diagnostics/tests/imports/ClassClash.txt

@@ -12,7 +12,6 @@ package a {
     }
 }
 
-
 // -- Module: <m2> --
 package
 
@@ -27,13 +26,11 @@ package a {
     }
 }
 
-
 // -- Module: <m3> --
 package
 
 public fun test(/*0*/ b: a.B): kotlin.Unit
 
-
 // -- Module: <top_m1> --
 package
 
@@ -45,7 +42,6 @@ public final class B {
     public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
 
-
 // -- Module: <top_m2> --
 package
 
@@ -57,9 +53,9 @@ public final class B {
     public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
 
-
 // -- Module: <top_m3> --
 package
 
 public fun test(/*0*/ b: B): kotlin.Unit
 public fun test2(/*0*/ b: B): kotlin.Unit
+