Miscellaneous ansible-test updates. (#27937)

* Add keep alives to ansible-test ssh delegation.
* Improve ansible-test JSON parsing error messages.
* Increase ansible-test delegation sleep and retry.
* Update ansible-test to recognize .psm1 files.

test/runner/lib/http.py

@@ -86,7 +86,7 @@ class HttpClient(object):
         stdout, _ = run_command(self.args, cmd, capture=True, always=self.always, cmd_verbosity=2)
 
         if self.args.explain and not self.always:
-            return HttpResponse(200, '')
+            return HttpResponse(method, url, 200, '')
 
         header, body = stdout.split('\r\n\r\n', 1)
 
@@ -95,16 +95,20 @@ class HttpClient(object):
         http_response = first_line.split(' ')
         status_code = int(http_response[1])
 
-        return HttpResponse(status_code, body)
+        return HttpResponse(method, url, status_code, body)
 
 
 class HttpResponse(object):
     """HTTP response from curl."""
-    def __init__(self, status_code, response):
+    def __init__(self, method, url, status_code, response):
         """
+        :type method: str
+        :type url: str
         :type status_code: int
         :type response: str
         """
+        self.method = method
+        self.url = url
         self.status_code = status_code
         self.response = response
 
@@ -115,7 +119,7 @@ class HttpResponse(object):
         try:
             return json.loads(self.response)
         except ValueError:
-            raise HttpError(self.status_code, 'Cannot parse response as JSON:\n%s' % self.response)
+            raise HttpError(self.status_code, 'Cannot parse response to %s %s as JSON:\n%s' % (self.method, self.url, self.response))
 
 
 class HttpError(ApplicationError):