fix: fallback hostname to ip like add_target and get_target

[nic-6443]

Because when using add_target and get_target, if hostname is not specified, it will fallback to ip:

lua-resty-healthcheck/lib/resty/healthcheck.lua

Lines 490 to 493 in f1e644c

	function checker:add_target(ip, port, hostname, is_healthy, hostheader, tbl_meta)
	ip = tostring(assert(ip, "no ip address provided"))
	port = assert(tonumber(port), "no port number provided")
	hostname = hostname or ip

lua-resty-healthcheck/lib/resty/healthcheck.lua

Line 473 in f1e644c

hostname = hostname or ip

However, the same logic is missing in the incr_counter function. This causes the hostname to be missing in the counter key in the shared memory when using the report_http_status function to report passive health check data, which further results in the get_target_list function being unable to correctly retrieve the counter data:

The screenshot above shows the data in the shared dict when using passive health. It can be seen that all entries in `target_list` contain `hostname`. However, because the `incr_counter` lacks fallback code for `hostname`, both the counter and state are recorded in the shared memory key that does not contain `hostname`.

lua-resty-healthcheck/lib/resty/healthcheck.lua

Lines 1842 to 1849 in f1e644c

	local counter = self.shm:get(key_for(self.TARGET_COUNTER,
	target.ip, target.port, target.hostname))
	target.counter = {
	success = ctr_get(counter, CTR_SUCCESS),
	http_failure = ctr_get(counter, CTR_HTTP),
	tcp_failure = ctr_get(counter, CTR_TCP),
	timeout_failure = ctr_get(counter, CTR_TIMEOUT),
	}

However, get_target_list needs to retrieve data from the shared dict through a key that includes hostname. Since the keys do not match, it cannot work.

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[shreemaan-abhishek]

why this change?

[nic-6443]

lua-resty-healthcheck/lib/resty/healthcheck.lua

Line 1361 in f1e644c

self:log(DEBUG, "event: target status '", hostname or "", "(", ip, ":",

Actually, there is no space between hostname and ( .

Because the assertion is no_error_log, the mistake wasn't detected. So the previous test was actually ineffective; if there was really a problem with the code, this test wouldn't have found it.

[shreemaan-abhishek]

nice!

[shreemaan-abhishek]

great PR!