[TEST-ONLY] Relax the caching tests

Relax the caching tests to allow changes to swift scanner to not passing
paths to clang modules on command-line.

Author: cachemeifyoucan

Tests/SwiftDriverTests/CachingBuildTests.swift

@@ -162,8 +162,6 @@ private func checkCachingBuildJobDependencies(job: Job,
     let clangDependencyModulePath =
       TypedVirtualPath(file: clangDependencyModulePathString, type: .pcm)
     XCTAssertTrue(job.inputs.contains(clangDependencyModulePath))
-    XCTAssertTrue(job.commandLine.contains(
-      .flag(String("-fmodule-file=\(dependencyId.moduleName)=\(clangDependencyModulePathString)"))))
     XCTAssertTrue(job.commandLine.contains(
       .flag(String("-fmodule-file-cache-key"))))
     let cacheKey = try XCTUnwrap(clangDependencyDetails.moduleCacheKey)