fix(docker): Ignore local build and lint cache (#1994)

These should not be replicated to docker contexts as they are local to
the build host.  In addition, the golangci-lint currently doesn't assume
the host user nor add other group read permissions when writing files,
so this causes permission errors when other docker processes attempt to
copy the files.

.dockerignore

@@ -11,5 +11,10 @@ docs/
 networks/
 scratch/
 
+# Ignore build cache directories to avoid
+# errors when addings these to docker images
+build/.cache
+build/.golangci-lint
+
 go.work
 go.work.sum