Remove and ignore go workspace files

There's no watertight advice on whether to check go workspace files in
(go.work and go.work.sum), but generally they are regarded as
local. See golang/go#53502 as the most
central discussion on this).

Here, they tend to get in the way, because `go.work.sum` is not
updated by `go mod tidy` and isn't subject to (the default) `-mod
readonly`. In the absence of a clear benefit to checking them in, I'm
removing them.

Signed-off-by: Michael Bridgen <[email protected]>

Author: squaremo

.gitignore

@@ -23,6 +23,8 @@ testbin/*
 *.swp
 *.swo
 *~
+go.work
+go.work.sum
 
 # credentials used for accessing GitHub during container build
 .netrc