🔥(ci) drop the requests dependency from the gitmoji rule

The rule downloaded the gitmoji list with requests, so lint-git had to install
that package before the linter could run. urllib.request is in the standard
library and answers the same call, leaving one fewer package fetched on the
runner before the job's own command starts.

gitlint/gitlint_emoji.py

@@ -3,14 +3,14 @@ Gitlint extra rule to validate that the message title is of the form
 "<gitmoji>(<scope>) <subject>"
 """
 
-from __future__ import unicode_literals
-
+import json
 import re
-
-import requests
+import urllib.request
 
 from gitlint.rules import CommitMessageTitle, LineRule, RuleViolation
 
+GITMOJIS_URL = "https://raw.githubusercontent.com/carloscuesta/gitmoji/master/packages/gitmojis/src/gitmojis.json"
+
 
 class GitmojiTitle(LineRule):
     """
@@ -28,9 +28,8 @@ class GitmojiTitle(LineRule):
         Download the list possible gitmojis from the project's github repository and check that
         title contains one of them.
         """
-        gitmojis = requests.get(
-            "https://raw.githubusercontent.com/carloscuesta/gitmoji/master/packages/gitmojis/src/gitmojis.json"
-        ).json()["gitmojis"]
+        with urllib.request.urlopen(GITMOJIS_URL, timeout=10) as response:
+            gitmojis = json.load(response)["gitmojis"]
         emojis = [item["emoji"] for item in gitmojis]
         pattern = r"^({:s})\(.*\)\s[a-z].*$".format("|".join(emojis))
         if not re.search(pattern, title):