FIR IDE: move FIR IDE completion tests to idea-fir module

idea/idea-completion/testData/basic/common/lambdaSignature/ParameterName2.kt

@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun bar() {
     val handler = { i: Int, <caret> }
 }

idea/idea-completion/testData/basic/common/lambdaSignature/ParameterName3.kt

@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun bar() {
     val handler = { i, <caret> }
 }

idea/idea-completion/testData/basic/common/lambdaSignature/ParameterName5.kt

@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun bar() {
     val handler = { p1: Int, p2: List<String>, <caret> }
 }