treewide: switch to gomod and bump everything

This switches version resolution from fietsje to gomod and updates
all Go dependencies. It also bumps rules_go (required by gVisor) and
switches the Gazelle naming convention from go_default_xxx to the
standard Bazel convention of the default target having the package
name.

Since Kubernetes dropped upstream Bazel support and doesn't check in
all generated files I manually pregenerated the OpenAPI spec. This
should be fixed, but because of the already-huge scope of this CL
and the rebase complexity this is not in here.

Change-Id: Iec8ea613d06946882426c2f9fad5bda7e8aaf833
Reviewed-on: https://review.monogon.dev/c/monogon/+/639
Reviewed-by: Sergiusz Bazanski <serge@monogon.tech>
Reviewed-by: Leopold Schabel <leo@nexantic.com>
diff --git a/metropolis/proto/private/BUILD.bazel b/metropolis/proto/private/BUILD.bazel
index 8f7cd50..57b7ba4 100644
--- a/metropolis/proto/private/BUILD.bazel
+++ b/metropolis/proto/private/BUILD.bazel
@@ -16,7 +16,7 @@
 )
 
 go_library(
-    name = "go_default_library",
+    name = "private",
     embed = [":private_go_proto"],
     importpath = "source.monogon.dev/metropolis/proto/private",
     visibility = ["//metropolis:__subpackages__"],