[LL FIR] AbstractInnerDeclarationsResolvePhaseTest use .txt instead of .fir.txt

^KT-60728

analysis/low-level-api-fir/testdata/innerDeclarationsResolve/lambda.fir.txt

@@ -1,23 +0,0 @@
-FILE: lambda.kt
-    public final inline [BODY_RESOLVE] fun <T, R> with([BODY_RESOLVE] receiver: R|T|, [BODY_RESOLVE] block: R|T.() -> R|): R|R| {
-        ^with R|<local>/block|.R|SubstitutionOverride<kotlin/Function1.invoke: R|R|>|(R|<local>/receiver|)
-    }
-    public final inline [BODY_RESOLVE] fun <T, R> R|T|.let([BODY_RESOLVE] block: R|(T) -> R|): R|R| {
-        ^let R|<local>/block|.R|SubstitutionOverride<kotlin/Function1.invoke: R|R|>|(this@R|/let|)
-    }
-    public final [BODY_RESOLVE] class B : R|kotlin/Any| {
-        public [BODY_RESOLVE] constructor(): R|B| {
-            super<R|kotlin/Any|>()
-        }
-
-        public final [BODY_RESOLVE] fun foo([BODY_RESOLVE] a: R|kotlin/Int|): R|kotlin/String| {
-            ^foo R|/with|<R|kotlin/Int|, R|kotlin/String|>(R|<local>/a|, <L> = [BODY_RESOLVE] with@fun R|kotlin/Int|.<anonymous>(): R|kotlin/String| <kind=UNKNOWN>  {
-                ^ this@R|special/anonymous|.R|kotlin/Any.toString|().R|/let|<R|kotlin/String|, R|kotlin/String|>(<L> = [BODY_RESOLVE] let@fun <anonymous>([BODY_RESOLVE] it: R|kotlin/String|): R|kotlin/String| <kind=UNKNOWN>  {
-                    ^ R|<local>/it|
-                }
-                )
-            }
-            )
-        }
-
-    }

analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/resolve/AbstractInnerDeclarationsResolvePhaseTest.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2023 JetBrains s.r.o. and Kotlin Programming Language contributors.
  * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
  */
 
@@ -22,7 +22,7 @@ abstract class AbstractInnerDeclarationsResolvePhaseTest : AbstractLowLevelApiSi
         resolveWithClearCaches(ktFile) { firResolveSession ->
             val firFile = ktFile.getOrBuildFirOfType<FirFile>(firResolveSession)
             val actual = FirRenderer.withResolvePhase().renderElementAsString(firFile)
-            testServices.assertions.assertEqualsToTestDataFileSibling(actual, extension = ".fir.txt")
+            testServices.assertions.assertEqualsToTestDataFileSibling(actual)
         }
     }
 }
@@ -32,5 +32,5 @@ abstract class AbstractSourceInnerDeclarationsResolvePhaseTest : AbstractInnerDe
 }
 
 abstract class AbstractOutOfContentRootInnerDeclarationsResolvePhaseTest : AbstractInnerDeclarationsResolvePhaseTest() {
-    override val configurator = AnalysisApiFirOutOfContentRootTestConfigurator
+    override val configurator get() = AnalysisApiFirOutOfContentRootTestConfigurator
 }