KTIJ-26423 [AA] Remove FE10 tests for KtImportOptimizer

We don't plan to seriously support the FE10 implementation of
`KtImportsOptimizer` service, since it's not going to be used in IDE
(it has its own old version of import optimization logic)

generators/analysis-api-generator/tests/org/jetbrains/kotlin/generators/tests/analysis/api/analysisApi.kt

@@ -321,7 +321,7 @@ private fun AnalysisApiTestGroup.generateAnalysisApiComponentsTests() {
     component("importOptimizer") {
         test(
             AbstractAnalysisApiImportOptimizerTest::class,
-            filter = analysisSessionModeIs(AnalysisSessionMode.Normal),
+            filter = analysisSessionModeIs(AnalysisSessionMode.Normal) and frontendIs(FrontendKind.Fir),
         ) {
             model(it, "analyseImports")
         }