Adds a refactored bigip_monitor_http module. (#30998)

This patch refactors the bigip_monitor_http module to use REST
instead of SOAP. It additionally adds unit tests and current F5
code conventions.

Integration tests can be found here
* https://github.com/F5Networks/f5-ansible/blob/devel/test/integration/bigip_monitor_http.yaml
* https://github.com/F5Networks/f5-ansible/tree/devel/test/integration/targets/bigip_monitor_http/tasks

test/units/modules/network/f5/fixtures/load_ltm_monitor_http.json

@@ -0,0 +1,28 @@
+{
+  "kind": "tm:ltm:monitor:http:httpstate",
+  "name": "asdf",
+  "partition": "Common",
+  "fullPath": "/Common/asdf",
+  "generation": 0,
+  "selfLink": "https://localhost/mgmt/tm/ltm/monitor/http/~Common~asdf?ver=13.0.0",
+  "adaptive": "disabled",
+  "adaptiveDivergenceType": "relative",
+  "adaptiveDivergenceValue": 25,
+  "adaptiveLimit": 200,
+  "adaptiveSamplingTimespan": 300,
+  "defaultsFrom": "/Common/http",
+  "description": "this is a description",
+  "destination": "1.1.1.1:389",
+  "interval": 5,
+  "ipDscp": 0,
+  "manualResume": "disabled",
+  "password": "$M$7T$DpzEUVHt5rKkAfqrBh1PTA==",
+  "recv": "hello world",
+  "reverse": "enabled",
+  "send": "GET /\\r\\n",
+  "timeUntilUp": 0,
+  "timeout": 16,
+  "transparent": "disabled",
+  "upInterval": 0,
+  "username": "john"
+}