workspace: use new-style proto toolchain resolution

Change-Id: I6b8dc9f3cd0d365527464fdd518f8ad76a4f8d5d
Reviewed-on: https://review.monogon.dev/c/monogon/+/3235
Tested-by: Jenkins CI
Reviewed-by: Leopold Schabel <leo@monogon.tech>
Reviewed-by: Lorenz Brun <lorenz@monogon.tech>
diff --git a/.bazelrc b/.bazelrc
index 77d25d8..7f6b151 100644
--- a/.bazelrc
+++ b/.bazelrc
@@ -51,6 +51,9 @@
 # Use new-style C++ toolchain resolution.
 build --incompatible_enable_cc_toolchain_resolution
 
+# Use new-style proto toolchain resolution.
+build --incompatible_enable_proto_toolchain_resolution
+
 # In our monorepo, we mostly ignore the host platform since we bring our own
 # execution environment. However, we still need to run a small number of tools
 # such as gazelle. We can just use rules_go's pure-Go platform. Attempting to