fix: start GRPCWebServer in goroutine (backport cosmos#9704) (cosmos#…

…9719)

* fix: start GRPCWebServer in goroutine (cosmos#9704)

so it don't block other code from executing.

Closes cosmos#9703

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(cherry picked from commit d5674a5)

# Conflicts:
#	CHANGELOG.md

* fix changelog

Co-authored-by: yihuang <huang@crypto.com>
Co-authored-by: Robert Zaremba <robert@zaremba.ch>

CHANGELOG.md

@@ -35,6 +35,11 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 # Changelog
 
+## [v0.43.0-rc2](https://github.com/cosmos/cosmos-sdk/releases/tag/v0.43.0-rc2) - 2021-07-19
+
+### Bug Fixes
+
+* (server) [#9704](https://github.com/cosmos/cosmos-sdk/pull/9704) Start GRPCWebServer in goroutine, avoid blocking other services from starting.
 
 ## [v0.43.0-rc1](https://github.com/cosmos/cosmos-sdk/releases/tag/v0.43.0-rc1) - 2021-07-14