third_party/go: fix `go mod tidy`
This makes our root repository somewhat more gomod-compliant, to the
point where we can run `go mod tidy` to manage dependencies.
The generated placeholder files turn their parent paths into enough of a
Go package that the go tooling is appeased, but they are ignored by
Gazelle.
Ideally, we will generate these placeholders automatically before
running `go mod tidy` and gitignore them, but this will do as a first
pass.
We also remove some unused dependencies which got caught by `go mod
tidy`.
Change-Id: I81e7e92a45f22c8ef9c92207f67a5bd6cc773da5
Reviewed-on: https://review.monogon.dev/c/monogon/+/652
Reviewed-by: Lorenz Brun <lorenz@monogon.tech>
Reviewed-by: Leopold Schabel <leo@nexantic.com>
diff --git a/BUILD b/BUILD
index 8244c90..a6e19d7 100644
--- a/BUILD
+++ b/BUILD
@@ -3,6 +3,7 @@
# gazelle:prefix source.monogon.dev
# gazelle:go_naming_convention import
+# gazelle:exclude **/gomod-generated-placeholder.go
gazelle(name = "gazelle")
gazelle(