[JVM+IR] Unify new debugger tests expectations

This commit unifies the expectation format between the stepping and
LVT tests in the new debugging test harness.

Furthermore, it introduces a compression of runs of locations without
linenumbers. These default to showing as bytecode offsets from
previous line number, which overspecifies the tests: the bytecodes
chosen should not be constrained by a debugging step test.

compiler/testData/debug/localVariables/catchClause.kt

@@ -10,10 +10,10 @@ fun box() {
 }
 
 // LOCAL VARIABLES
-// TestKt:3:
-// TestKt:4:
-// TestKt:5: a:int=1:int
-// TestKt:6: a:int=0:int
-// TestKt:7:
-// TestKt:8: e:java.lang.Throwable=java.lang.ArithmeticException
-// TestKt:10:
+// test.kt:3 box:
+// test.kt:4 box:
+// test.kt:5 box: a:int=1:int
+// test.kt:6 box: a:int=0:int
+// test.kt:7 box:
+// test.kt:8 box: e:java.lang.Throwable=java.lang.ArithmeticException
+// test.kt:10 box: