fix(health): use TCP dialing instead of ping

- `HEALTH_TARGET_ADDRESS` to replace `HEALTH_ADDRESS_TO_PING`
- Remove `github.com/go-ping/ping` dependency
- Dial TCP the target address, appending `:443` if port is not set

internal/configuration/settings/settings_test.go

@@ -66,7 +66,7 @@ func Test_Settings_String(t *testing.T) {
 |   └── Log level: INFO
 ├── Health settings:
 |   ├── Server listening address: 127.0.0.1:9999
-|   ├── Address to ping: github.com
+|   ├── Target address: github.com:443
 |   └── VPN wait durations:
 |       ├── Initial duration: 6s
 |       └── Additional duration: 5s