IR text tests: Unmute tests that have main function

Don't use `main` function in these tests, because `main` function
has specific mangling rules in JVM. Use other function name.

^KT-57755

compiler/testData/ir/irText/expressions/argumentMappedWithError.kt

@@ -1,14 +1,11 @@
 // FIR_IDENTICAL
 
-// MUTE_SIGNATURE_COMPARISON_K2: JVM_IR
-// ^ KT-57755 : Fix computing a mangled name for the `main` function
-
 fun <R : Number> Number.convert(): R = TODO()
 
 fun foo(arg: Number) {
 }
 
-fun main(args: Array<String>) {
+fun runMe(args: Array<String>) {
     val x: Int = 0
     foo(x.convert())
 }