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/suspendConversionForExtensionFunction.kt

@@ -1,10 +1,7 @@
 // SKIP_KT_DUMP
 // !LANGUAGE: +SuspendConversion
 
-// MUTE_SIGNATURE_COMPARISON_K2: JVM_IR
-// ^ KT-57755: Fix computing a mangled name for the `main` function
-
-fun main() {
+fun runMe() {
     val foo: String.(suspend () -> Unit) -> Unit = {}
     val f: () -> Unit = {}
     "".foo(f)