internal/lsp: replace mistaken "break" with "continue"
internal/lsp: replace mistaken "break" with "continue"

I had meant to continue instead of break this loop. This caused us to
invalidate all IDs (except for those for one file) every time a snapshot
was cloned.

Picked up a staticcheck fix along the way.

Change-Id: I8fb3b2bdd6b58ac21130e01cb0d32fa6a57e6b73
Reviewed-on: https://go-review.googlesource.com/c/tools/+/221103
Run-TryBot: Rebecca Stambler <d7cf11e5f299d88ea8348366a9fc4f7c335c3afa@golang.org>
Reviewed-by: Rohan Challa <9671c73253cee9b18b8df367e3e627fab2863fe8@golang.org>

golang/tools,golang/tools,golang/tools,golang/tools,golang/tools