Swift: Update mention of manifest file in docs

Author: henrymercer

swift/README.md

@@ -13,7 +13,7 @@ bazel run //swift:create-extractor-pack
 which will install `swift/extractor-pack`.
 
 Using `--search-path=swift/extractor-pack` will then pick up the Swift extractor. You can also use
-`--search-path=.`, as the extractor pack is mentioned in the root `.codeqlmanifest.json`.
+`--search-path=.`, as the extractor pack is mentioned in the root `.codeql-workspace.json`.
 
 Notice you can run `bazel run :create-extractor-pack` if you already are in the `swift` directory.