Add num of tasks running health validation

[italux]

Description

In some cases, I've seen that the number of running tasks are under the tasks.max configuration number which can leverage partitions to become without any consumer and to avoid this behavior I'm adding validation to the handle_task_healthcheck comparing the number of running tasks on the container obtained from get_connectors_health with the desired tasks.max

This validation is enabled by default but I've added a new param to disable the validation passing --failure-less-tasks False or setting HEALTHCHECK_FAILURE_LESS_TASKS=False

• Logging samples with DEBUG level

2021-06-04 00:38:44.293 [   INFO] - Initializing healthcheck server...
2021-06-04 00:38:44.296 [   INFO] - Healthcheck server started at: http://localhost:18083
2021-06-04 00:38:44.296 [   INFO] - ------------------------------------------------
2021-06-04 00:38:45.137 [  DEBUG] - Starting new HTTP connection (1): localhost:8083
2021-06-04 00:38:46.202 [  DEBUG] - http://localhost:8083 "GET /connectors HTTP/1.1" 200 25
2021-06-04 00:38:46.206 [  DEBUG] - Starting new HTTP connection (1): localhost:8083
2021-06-04 00:38:47.071 [  DEBUG] - http://localhost:8083 "GET /connectors/ProtoElasticConnector/status HTTP/1.1" 200 481
2021-06-04 00:38:47.074 [  DEBUG] - Starting new HTTP connection (1): localhost:8083
2021-06-04 00:38:47.918 [  DEBUG] - http://localhost:8083 "GET /connectors/ProtoElasticConnector HTTP/1.1" 200 1472
2021-06-04 00:38:47.919 [   INFO] - Connector 'ProtoElasticConnector' is healthy in state: RUNNING
2021-06-04 00:38:47.919 [  DEBUG] - Connector 'ProtoElasticConnector' state: RUNNING tasks running: '6' desired: '6'
2021-06-04 00:38:47.919 [   INFO] - Connector 'ProtoElasticConnector' task '0' is healthy in state: RUNNING
2021-06-04 00:38:47.919 [   INFO] - Connector 'ProtoElasticConnector' task '1' is healthy in state: RUNNING
2021-06-04 00:38:47.919 [   INFO] - Connector 'ProtoElasticConnector' task '2' is healthy in state: RUNNING
2021-06-04 00:38:47.919 [   INFO] - Connector 'ProtoElasticConnector' task '3' is healthy in state: RUNNING
2021-06-04 00:38:47.919 [   INFO] - Connector 'ProtoElasticConnector' task '4' is healthy in state: RUNNING
2021-06-04 00:38:47.919 [   INFO] - Connector 'ProtoElasticConnector' task '5' is healthy in state: RUNNING
2021-06-04 00:38:47.919 [   INFO] - ------------------------------------------------

[italux]

@devshawn Do you think this is useful?