KTIJ-26423 [AA] Get rid of local declarations in KtFirImportOptimizer

Adjust `computeImportableName` to return null for when passed symbol
is local

analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/utils/firUtils.kt

@@ -54,6 +54,8 @@ internal fun KtTypeNullability.toConeNullability() = when (this) {
  * @return An [FqName] by which this symbol can be imported (if it is possible)
  */
 internal fun FirCallableSymbol<*>.computeImportableName(useSiteSession: FirSession): FqName? {
+    if (callableId.isLocal) return null
+
     // if classId == null, callable is topLevel
     val containingClassId = callableId.classId
         ?: return callableId.asSingleFqName()