git tracks content, not files. if two files are the same (or very much the same) git recognizes them as copied. there shouldn’t be any implications from this
in your case both files were identical (100 %), so git has no possibility to know if the file was copied, or just accidentally happened to be the same.
don’t worry, git only stores snapshots of the tree to the repository. you can control copy and rename detection for git log with parameters -C and -M, git will then try harder to find renames/copies