Revert "Add test case"

This reverts commit c75cfd4.

Author: rintaro

Tests/SwiftDriverTests/SwiftDriverTests.swift

@@ -6776,7 +6776,6 @@ final class SwiftDriverTests: XCTestCase {
 
     try withTemporaryDirectory { tmpDir in
       var driver = try Driver(args: ["swiftc", "-typecheck", "foo.swift"],
-                              integratedDriver: false,
                               compilerExecutableDir: tmpDir)
       guard driver.isFrontendArgSupported(.externalPluginPath) else {
         return
@@ -6819,27 +6818,6 @@ final class SwiftDriverTests: XCTestCase {
     }
   }
 
-  func testExternalPluginPathsDisabled() throws {
-#if !os(macOS)
-    throw XCTSkip("Supported only in macOS")
-#endif
-
-    try withTemporaryDirectory { tmpDir in
-      var driver = try Driver(args: ["swiftc", "-typecheck", "foo.swift"],
-                              integratedDriver: true,
-                              compilerExecutableDir: tmpDir)
-      guard driver.isFrontendArgSupported(.externalPluginPath) else {
-        return
-      }
-
-      let jobs = try driver.planBuild().removingAutolinkExtractJobs()
-      XCTAssertEqual(jobs.count, 1)
-      let job = jobs.first!
-
-      XCTAssertFalse(job.commandLine.contains(.flag("-external-plugin-path")))
-    }
-  }
-
   func testClangModuleValidateOnce() throws {
     let flagTest = try Driver(args: ["swiftc", "-typecheck", "foo.swift"])
     guard flagTest.isFrontendArgSupported(.clangBuildSessionFile),