FIR: Rename SAM constructor parameter name from "block" to "function".

This matches FE 1.0 (see
core/descriptors/src/org/jetbrains/kotlin/resolve/sam/samConstructorUtils.kt).

analysis/analysis-api/testData/analysisSession/resolveCall/samConstructorCall.txt

@@ -1,4 +1,4 @@
 KtFunctionCall:
-argumentMapping = { {x: Int, y: Int -> 1} -> (block: kotlin.Function2<ft<kotlin.Int, kotlin.Int?>, ft<kotlin.Int, kotlin.Int?>, kotlin.Int>) }
-targetFunction = java/util/Comparator(block: kotlin.Function2<ft<kotlin.Int, kotlin.Int?>, ft<kotlin.Int, kotlin.Int?>, kotlin.Int>): java.util.Comparator<ft<kotlin.Int, kotlin.Int?>>
+argumentMapping = { {x: Int, y: Int -> 1} -> (function: kotlin.Function2<ft<kotlin.Int, kotlin.Int?>, ft<kotlin.Int, kotlin.Int?>, kotlin.Int>) }
+targetFunction = java/util/Comparator(function: kotlin.Function2<ft<kotlin.Int, kotlin.Int?>, ft<kotlin.Int, kotlin.Int?>, kotlin.Int>): java.util.Comparator<ft<kotlin.Int, kotlin.Int?>>
 substitutor = <map substitutor: {FirTypeParameterSymbol T=ft<kotlin/Int, kotlin/Int?>}>

analysis/analysis-api/testData/referenceResolve/SamConstructor.txt

@@ -1,2 +1,2 @@
 Resolved to:
-0: (in java.util) fun <T : kotlin.Any!> Comparator(block: (T!, T!) -> kotlin.Int): java.util.Comparator<T>
+0: (in java.util) fun <T : kotlin.Any!> Comparator(function: (T!, T!) -> kotlin.Int): java.util.Comparator<T>

analysis/analysis-api/testData/referenceResolve/SamConstructorTypeArguments.txt

@@ -1,2 +1,2 @@
 Resolved to:
-0: (in java.util) fun <T : kotlin.Any!> Comparator(block: (T!, T!) -> kotlin.Int): java.util.Comparator<T>
+0: (in java.util) fun <T : kotlin.Any!> Comparator(function: (T!, T!) -> kotlin.Int): java.util.Comparator<T>

analysis/analysis-api/testData/symbols/symbolByReference/samConstructor.txt

@@ -8,6 +8,6 @@ KtFirSamConstructorSymbol:
   receiverType: null
   symbolKind: SAM_CONSTRUCTOR
   valueParameters: [
-    KtFirValueParameterSymbol(block)
+    KtFirValueParameterSymbol(function)
   ]
   deprecationStatus: null