build: correct the install rule for swiftdocs (#1137)
build: correct the install rule for swiftdocs (#1137)

A copy-paste error resulted in copying the swiftmodule over the
swiftdoc.  Correct this.  Thanks to @pschuh who originally spotted the
mistake!
tensorflow/swift-apis,tensorflow/swift-apis,tensorflow/swift-apis,tensorflow/swift-apis,tensorflow/swift-apis