chore: upgrade grpc-erl to 0.6.12

grpc-erl 0.6.12 doesn't start dependent apps lazily anymore, as it was not deadlock safe.

changes/ce/fix-12078.en.md

@@ -0,0 +1,3 @@
+Upgrade grpc-erl to 0.6.12
+
+grpc-erl 0.6.12 fixes a potential deadlock that was possible because grpc client started dependent apps lazily.

mix.exs

@@ -57,7 +57,7 @@ defmodule EMQXUmbrella.MixProject do
       {:rocksdb, github: "emqx/erlang-rocksdb", tag: "1.8.0-emqx-1", override: true},
       {:ekka, github: "emqx/ekka", tag: "0.15.16", override: true},
       {:gen_rpc, github: "emqx/gen_rpc", tag: "3.2.2", override: true},
-      {:grpc, github: "emqx/grpc-erl", tag: "0.6.8", override: true},
+      {:grpc, github: "emqx/grpc-erl", tag: "0.6.12", override: true},
       {:minirest, github: "emqx/minirest", tag: "1.3.14", override: true},
       {:ecpool, github: "emqx/ecpool", tag: "0.5.4", override: true},
       {:replayq, github: "emqx/replayq", tag: "0.3.7", override: true},

rebar.config

@@ -64,7 +64,7 @@
     , {rocksdb, {git, "https://github.com/emqx/erlang-rocksdb", {tag, "1.8.0-emqx-1"}}}
     , {ekka, {git, "https://github.com/emqx/ekka", {tag, "0.15.16"}}}
     , {gen_rpc, {git, "https://github.com/emqx/gen_rpc", {tag, "3.2.2"}}}
-    , {grpc, {git, "https://github.com/emqx/grpc-erl", {tag, "0.6.8"}}}
+    , {grpc, {git, "https://github.com/emqx/grpc-erl", {tag, "0.6.12"}}}
     , {minirest, {git, "https://github.com/emqx/minirest", {tag, "1.3.14"}}}
     , {ecpool, {git, "https://github.com/emqx/ecpool", {tag, "0.5.4"}}}
     , {replayq, {git, "https://github.com/emqx/replayq.git", {tag, "0.3.7"}}}