Remove obsolete assertion in ExpressionCodegen

With the mangling added in 488418d960, there's no longer any risk in
writing "special" function name ("<anonymous>" in this case) to the
local variable table.

 #KT-34356 Fixed

js/js.tests/test/org/jetbrains/kotlin/js/test/ir/semantics/IrJsCodegenBoxTestGenerated.java

@@ -9016,6 +9016,11 @@ public class IrJsCodegenBoxTestGenerated extends AbstractIrJsCodegenBoxTest {
                 runTest("compiler/testData/codegen/box/functions/functionExpression/functionLiteralExpression.kt");
             }
 
+            @TestMetadata("insideGenericLambda.kt")
+            public void testInsideGenericLambda() throws Exception {
+                runTest("compiler/testData/codegen/box/functions/functionExpression/insideGenericLambda.kt");
+            }
+
             @TestMetadata("underscoreParameters.kt")
             public void testUnderscoreParameters() throws Exception {
                 runTest("compiler/testData/codegen/box/functions/functionExpression/underscoreParameters.kt");

js/js.tests/test/org/jetbrains/kotlin/js/test/semantics/JsCodegenBoxTestGenerated.java

@@ -10101,6 +10101,11 @@ public class JsCodegenBoxTestGenerated extends AbstractJsCodegenBoxTest {
                 runTest("compiler/testData/codegen/box/functions/functionExpression/functionLiteralExpression.kt");
             }
 
+            @TestMetadata("insideGenericLambda.kt")
+            public void testInsideGenericLambda() throws Exception {
+                runTest("compiler/testData/codegen/box/functions/functionExpression/insideGenericLambda.kt");
+            }
+
             @TestMetadata("underscoreParameters.kt")
             public void testUnderscoreParameters() throws Exception {
                 runTest("compiler/testData/codegen/box/functions/functionExpression/underscoreParameters.kt");