test: add basic integration test for CRUD (#339)

**Issue number:**
[ADDON-78485](https://splunk.atlassian.net/browse/ADDON-78485)

### PR Type

**What kind of change does this PR introduce?**
* [ ] Feature
* [ ] Bug Fix
* [ ] Refactoring (no functional or API changes)
* [ ] Documentation Update
* [x] Maintenance (dependency updates, CI, etc.)

## Summary

### Changes
Add test for basic CRUD operation for RestHandler.

### User experience

No impact.

## Checklist

If an item doesn't apply to your changes, leave it unchecked.

### Review

* [x] self-review - I have performed a self-review of this change
according to the [development
guidelines](https://splunk.github.io/addonfactory-ucc-generator/contributing/#development-guidelines)
* [ ] Changes are documented. The documentation is understandable,
examples work [(more
info)](https://splunk.github.io/addonfactory-ucc-generator/contributing/#documentation-guidelines)
* [x] PR title and description follows the [contributing
principles](https://splunk.github.io/addonfactory-ucc-generator/contributing/#pull-requests)
* [ ] meeting - I have scheduled a meeting or recorded a demo to explain
these changes (if there is a video, put a link below and in the ticket)

### Tests

See [the testing
doc](https://splunk.github.io/addonfactory-ucc-generator/contributing/#build-and-test).

* [ ] Unit - tests have been added/modified to cover the changes
* [x] Integration - tests have been added/modified to cover the changes
* [ ] Smoke - tests have been added/modified to cover the changes
* [ ] UI - tests have been added/modified to cover the changes
* [ ] coverage - I have checked the code coverage of my changes [(see
more)](https://splunk.github.io/addonfactory-ucc-generator/contributing/#checking-the-code-coverage)

Author: sgoral-splunk

tests/integration/test_rest_handler_handler.py

@@ -13,6 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
+
 from datetime import datetime
 from time import sleep
 from typing import List, Any
@@ -48,6 +49,95 @@ def _cookie_header():
     return f"splunkd_8000={session_key}"
 
 
+def test_basic_crud_operations():
+    """
+    Test basic CRUD operations for splunktaucclib.rest_handler.handler.RestHandler
+    """
+    input_name = "atest_in_ok"
+
+    #  CREATE
+    response = requests.post(
+        f"https://{host}:{management_port}/servicesNS/-/demo/demo_demo?output_mode=json",
+        data={"name": input_name, "interval": "123"},
+        headers={
+            "accept": "application/json",
+            "Content-Type": "application/x-www-form-urlencoded",
+        },
+        auth=HTTPBasicAuth(admin, admin_password),
+        verify=False,
+    )
+    assert response.status_code == 201
+
+    #  GET
+    response = requests.get(
+        f"https://{host}:{management_port}/servicesNS/-/demo/demo_demo/{input_name}?output_mode=json",
+        auth=HTTPBasicAuth(admin, admin_password),
+        headers={
+            "accept": "application/json",
+            "Content-Type": "application/x-www-form-urlencoded",
+        },
+        verify=False,
+    )
+    entry = response.json().get("entry")
+    assert len(entry) == 1
+    assert entry[0].get("name") == input_name
+    assert entry[0].get("content").get("interval") == "123"
+    assert response.status_code == 200
+
+    #  ALL
+    response = requests.get(
+        f"https://{host}:{management_port}/servicesNS/-/demo/demo_demo/?output_mode=json",
+        auth=HTTPBasicAuth(admin, admin_password),
+        verify=False,
+    )
+    entries = response.json().get("entry")
+    names = [entry.get("name") for entry in entries]
+
+    assert len(entries) == 2
+    assert set(names) == {"test_input", input_name}
+    assert response.status_code == 200
+
+    #  UPDATE
+    new_interval = "111"
+    response = requests.post(
+        f"https://{host}:{management_port}/servicesNS/-/demo/demo_demo/{input_name}?output_mode=json",
+        data={"interval": new_interval},
+        auth=HTTPBasicAuth(admin, admin_password),
+        verify=False,
+    )
+
+    entry = response.json().get("entry")
+    interval = entry[0].get("content").get("interval")
+    assert response.status_code == 200
+    assert interval == new_interval
+
+    #  DELETE
+    response = requests.delete(
+        f"https://{host}:{management_port}/servicesNS/-/demo/demo_demo/{input_name}?output_mode=json",
+        auth=HTTPBasicAuth(admin, admin_password),
+        verify=False,
+    )
+    entry = response.json().get("entry")
+
+    assert response.status_code == 200
+    assert len(entry) == 1
+
+    expected_msg = (
+        f"REST Error [404]: Not Found -- Could not find object id={input_name}"
+    )
+    response = requests.get(
+        f"https://{host}:{management_port}/servicesNS/-/demo/demo_demo/{input_name}?output_mode=json",
+        auth=HTTPBasicAuth(admin, admin_password),
+        headers={
+            "accept": "application/json",
+            "Content-Type": "application/x-www-form-urlencoded",
+        },
+        verify=False,
+    )
+    assert response.status_code == 500
+    assert expected_msg in response.text
+
+
 def test_inputs_api_call():
     try:
         response = requests.get(