(Same as #6289 )
This adds the information from `proc_lib:initial_call/1` and the
current stacktrace from the process info to `emqx_sys_mon:procinfo/1`
to aid in debugging some warnings with no context such as the
following:
```
2021-11-23T12:33:59.387818+00:00 [warning] info: [{old_heap_block_size,45988046},{heap_block_size,22177879},{mbuf_size,0},{stack_size,40},{old_heap_size,22354134},{heap_size,7106339}], line: 130, mfa: emqx_sys_mon:handle_info/2, msg: large_heap, procinfo: [{pid,<0.2667.0>},{memory,579763664},{total_heap_size,68510672},{heap_size,22177879},{stack_size,40},{min_heap_size,233},{initial_call,{proc_lib,init_p,5}},{current_function,{gen,do_call,4}},{registered_name,[]},{status,running},{message_queue_len,360945},{group_leader,<0.1660.0>},{priority,normal},{trap_exit,false},{reductions,16493271},{last_calls,false},{catchlevel,4},{trace,0},{suspending,[]},{sequential_trace_token,[]},{error_handler,error_handler}]
```
* Add more test cases for emqx_stats and emqx_os_mon
Fix test case error for emqx_ws_connection
* Add more test cases for emqx_sys_mon
* Update erlang otp to 22.1 for travis ci
* Delete readable=false for make ct
* Add unset_all_env for emqx_zone and update test cases
* Fix the Exit in testcases
* Fix Exit in emqx_mod_sup_SUITE
* Update testcases for log_tracer
* Fix Exit in emqx_protocol_SUITE
* Add will_acl_check
* Fix more Exits