[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/smartCasts/varnotnull/initialization.kt

@@ -4,5 +4,5 @@ fun foo() {
     // It is possible in principle to provide smart cast here
     v<!UNSAFE_CALL!>.<!>length
     v = null
-    <!OI;DEBUG_INFO_CONSTANT!>v<!><!UNSAFE_CALL!>.<!>length
-}
+    <!DEBUG_INFO_CONSTANT{OI}!>v<!><!UNSAFE_CALL!>.<!>length
+}