chore(deps) bump resty.healthcheck from 1.3.0 to 2.0.0

### Summary

* BREAKING: fallback for deprecated top-level field `type` is now removed
  (deprecated since `0.5.0`) [#56](Kong/lua-resty-healthcheck#56)
* BREAKING: Bump `lua-resty-worker-events` dependency to `2.0.0`. This makes
  a lot of the APIs in this library asynchronous as the worker events `post`
  and `post_local` won't anymore call `poll` on a running worker automatically,
  for more information, see:
  https://github.com/Kong/lua-resty-worker-events#200-16-september-2020
* BREAKING: tcp_failures can no longer be 0 on http(s) checks (unless http(s)_failures
  are also set to 0) [#55](Kong/lua-resty-healthcheck#55)
* feature: Added support for https_sni [#49](Kong/lua-resty-healthcheck#49)
* fix: properly log line numbers by using tail calls [#29](Kong/lua-resty-healthcheck#29)
* fix: when not providing a hostname, use IP [#48](Kong/lua-resty-healthcheck#48)
* fix: makefile; make install
* feature: added a status version field [#54](Kong/lua-resty-healthcheck#54)
* feature: add headers for probe request [#54](Kong/lua-resty-healthcheck#54)
* fix: exit early when reloading during a probe [#47](Kong/lua-resty-healthcheck#47)
* fix: prevent target-list from being nil, due to async behaviour [#44](Kong/lua-resty-healthcheck#44)
* fix: replace timer and node-wide locks with resty-timer, to prevent interval
  skips [#59](Kong/lua-resty-healthcheck#59)
* change: added additional logging on posting events [#25](Kong/lua-resty-healthcheck#25)
* fix: do not run out of timers during init/init_worker when adding a vast
  amount of targets [#57](Kong/lua-resty-healthcheck#57)
* fix: do not call on the module table, but use a method for locks. Also in
  [#57](Kong/lua-resty-healthcheck#57)

kong-2.2.1-0.rockspec

@@ -30,7 +30,7 @@ dependencies = {
   "lua_pack == 1.0.5",
   "lua-resty-dns-client == 5.1.0",
   "lua-resty-worker-events == 1.0.0",
-  "lua-resty-healthcheck == 1.3.0",
+  "lua-resty-healthcheck == 2.0.0",
   "lua-resty-cookie == 0.1.0",
   "lua-resty-mlcache == 2.5.0",
   "lua-messagepack == 0.5.2",

spec/01-unit/09-balancer_spec.lua

@@ -112,6 +112,7 @@ for _, consistency in ipairs({"strict", "eventual"}) do
 
       local passive_hc = utils.deep_copy(hc_defaults)
       passive_hc.passive.healthy.successes = 1
+      passive_hc.passive.unhealthy.tcp_failures = 1 -- 1 = required because http failures is 1 as well
       passive_hc.passive.unhealthy.http_failures = 1
 
       UPSTREAMS_FIXTURES = {