Fail fast when using old define=ssz=<value> (prysmaticlabs#9316)

* Fail fast when using old define=ssz=<value>

* remove print statement

.bazelrc

@@ -24,11 +24,6 @@ build --sandbox_default_allow_network=false
 build --workspace_status_command=./scripts/workspace_status.sh
 build --stamp
 
-# Use mainnet protobufs at runtime
-run --define ssz=mainnet
-test --define ssz=mainnet
-build --define ssz=mainnet
-
 # Prevent PATH changes from rebuilding when switching from IDE to command line.
 build --incompatible_strict_action_env
 test --incompatible_strict_action_env

tools/ssz.bzl

@@ -5,6 +5,9 @@ load(
 )
 
 def _ssz_go_proto_library_impl(ctx):
+    if ctx.var.get("ssz"):
+        fail("--define=ssz=<value> is no longer supported, please use --//proto:network=<value>")
+
     if ctx.attr.go_proto != None:
         go_proto = ctx.attr.go_proto
         input_files = go_proto[OutputGroupInfo].go_generated_srcs.to_list()