[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/alwaysNull.kt

@@ -3,12 +3,12 @@ fun foo(): String {
     var s: String?
     s = null
     <!DEBUG_INFO_CONSTANT!>s<!>?.length
-    <!OI;DEBUG_INFO_CONSTANT!>s<!><!UNSAFE_CALL!>.<!>length
+    <!DEBUG_INFO_CONSTANT{OI}!>s<!><!UNSAFE_CALL!>.<!>length
     if (<!SENSELESS_COMPARISON!><!DEBUG_INFO_CONSTANT!>s<!> == null<!>) return <!ALWAYS_NULL!>s<!>!!
     var t: String? = "y"
     if (t == null) t = "x"
     var x: Int? = null
-    if (x == null) <!TYPE_MISMATCH!><!OI;DEBUG_INFO_CONSTANT!>x<!> += null<!>
+    if (x == null) <!TYPE_MISMATCH!><!DEBUG_INFO_CONSTANT{OI}!>x<!> += null<!>
     return <!DEBUG_INFO_SMARTCAST!>t<!> + s
 }
 
@@ -16,8 +16,8 @@ fun String?.gav() {}
 
 fun bar(s: String?) {
     if (s != null) return
-    <!OI;DEBUG_INFO_CONSTANT!>s<!>.gav()
+    <!DEBUG_INFO_CONSTANT{OI}!>s<!>.gav()
     <!DEBUG_INFO_CONSTANT!>s<!> <!USELESS_CAST!>as? String<!>
     <!DEBUG_INFO_CONSTANT!>s<!> <!USELESS_CAST!>as String?<!>
     <!ALWAYS_NULL!>s<!> as String
-}
+}