chore(deps) bump luarocks 3.8.0 to 3.9.0 (#8700)

### Summary

#### What's new in LuaRocks 3.9.0:

* `builtin` build mode now always respects CC, CFLAGS and LDFLAGS
* Check that lua.h version matches the desired Lua version
* Check that the version of the Lua C library matches the desired Lua version
* Fixed deployment of non-wrapped binaries
* Fixed crash when `--lua-version` option is malformed
* Fixed help message for `--pin` option
* Unix: use native methods and don't always rely on $USER to determine user
* Windows: use native CLI tooling more
* macOS: support .tbd extension when checking for libraries
* macOS: add XCode SDK path to search paths
* macOS: add best-effort heuristic for library search using Homebrew paths
* macOS: avoid quoting issues with LIBFLAG
* macOS: deployment target is now 11.0 on macOS 11+
* added DragonFly BSD support
* LuaRocks test suite now runs on Lua 5.4 and LuaJIT
* Internal dependencies of standalone LuaRocks executable were bumped

.requirements

@@ -3,7 +3,7 @@ KONG_CONFLICTS=kong-enterprise-edition
 KONG_LICENSE="ASL 2.0"
 
 RESTY_VERSION=1.19.9.1
-RESTY_LUAROCKS_VERSION=3.8.0
+RESTY_LUAROCKS_VERSION=3.9.0
 RESTY_OPENSSL_VERSION=1.1.1n
 RESTY_PCRE_VERSION=8.45
 RESTY_LMDB_VERSION=master

CHANGELOG.md

@@ -72,7 +72,7 @@
   method now. [#8596](https://github.com/Kong/kong/pull/8596). If you have
   scripts that depend on it being `POST`, these scripts will need to be updated
   when updating to Kong 3.0.
-- Insert and update operations on duplicated target entities returns 409. 
+- Insert and update operations on duplicated target entities returns 409.
   [#8179](https://github.com/Kong/kong/pull/8179)
 
 #### PDK
@@ -115,7 +115,9 @@
 - Bumped inspect from 3.1.2 to 3.1.3
   [#8589](https://github.com/Kong/kong/pull/8589)
 - Bumped resty.acme from 0.7.2 to 0.8.0
-  [#8680](https://github.com/Kong/kong/pull/8680
+  [#8680](https://github.com/Kong/kong/pull/8680)
+- Bumped luarocks from 3.8.0 to 3.9.0
+  [#8700](https://github.com/Kong/kong/pull/8700)
 
 ### Additions