Fix an article in the text. It should be "an import".

PiperOrigin-RevId: 486938898
Change-Id: I50af8fbdecc923d9a13af1d8ca6c61b0eeecf7c8

Author: Googler

src/main/java/com/google/devtools/build/lib/bazel/rules/cpp/BazelCcImportRule.java

@@ -79,7 +79,7 @@ public Metadata getMetadata() {
 cc_import(
   name = "mylib",
   hdrs = ["mylib.h"],
-  # mylib.lib is a import library for mylib.dll which will be passed to linker
+  # mylib.lib is an import library for mylib.dll which will be passed to linker
   interface_library = "mylib.lib",
   # mylib.dll will be available for runtime
   shared_library = "mylib.dll",