m/c/metroctl: add prototext node-params option

This adds the node-params flag to metroctl install, which allows
advanced users to specify customized NodeParameters in a prototext file.
The cluster field gets overwritten by the existing logic.  As of now,
this is only useful for specifying network_config.

Change-Id: Ieccf208177bb49635a634e484c67e99e80792bda
Reviewed-on: https://review.monogon.dev/c/monogon/+/3700
Vouch-Run-CI: Lorenz Brun <lorenz@monogon.tech>
Reviewed-by: Lorenz Brun <lorenz@monogon.tech>
Tested-by: Jenkins CI
diff --git a/metropolis/cli/metroctl/BUILD.bazel b/metropolis/cli/metroctl/BUILD.bazel
index 43805df..024b96c 100644
--- a/metropolis/cli/metroctl/BUILD.bazel
+++ b/metropolis/cli/metroctl/BUILD.bazel
@@ -61,6 +61,7 @@
         "@io_k8s_client_go//pkg/apis/clientauthentication/v1:clientauthentication",
         "@io_k8s_utils//ptr",
         "@org_golang_google_grpc//:grpc",
+        "@org_golang_google_protobuf//encoding/prototext",
         "@org_golang_google_protobuf//proto",
         "@org_golang_google_protobuf//types/known/fieldmaskpb",
         "@org_golang_x_crypto//ssh",