[Gradle, JS] Remove redundant fixing names

- in case when target name is `jsLegacy` with enabled both mode, we should get `jsLegacyMain` and `jsLegacyTest`, and Gradle plugin creates targets `jsLegacyLegacy` and `jsLegacyIr`, schema is name+suffix where name can be any, KotlinJsTargetPreset's name is name+`Both` so in KotlinJsTargetPreset in `both` case we need remove only `Both` suffix

#KT-39213 Fixed

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/KotlinJsTargetPreset.kt

@@ -31,13 +31,11 @@ open class KotlinJsTargetPreset(
     override val platformType: KotlinPlatformType
         get() = KotlinPlatformType.js
 
-    override fun useDisambiguitionClassifierAsSourcesetNamePreffix() = false
+    override fun useDisambiguitionClassifierAsSourcesetNamePreffix() = irPreset == null
 
     override fun overrideDisambiguitionClassifierOnIdeImport(): String? = if (isMpp) {
         irPreset?.let {
-            name.removeJsCompilerSuffix(KotlinJsCompilerType.LEGACY)
-                .removeJsCompilerSuffix(KotlinJsCompilerType.IR)
-                .removeJsCompilerSuffix(KotlinJsCompilerType.BOTH)
+            name.removeJsCompilerSuffix(KotlinJsCompilerType.BOTH)
         }
     } else {
         null