Set page size to 100 to reduce requests required to Github API to 1/3

- Default is 30. So number of paginated requests required to get all
  items (commits, files) will reduce by 67%

- No need to increase page size for the get tree Github API request from
  `get_markdown_files'

  Get tree Github API doesn't support pagination and return 100K items
  in response. This should be way more than enough for our current
  use-cases

src/khoj/processor/github/github_to_jsonl.py

@@ -117,11 +117,12 @@ class GithubToJsonl(TextToJsonl):
         # Get commit messages from the repository using the Github API
         commits_url = f"{self.repo_url}/commits"
         headers = {"Authorization": f"token {self.config.pat_token}"}
+        params = {"per_page": 100}
         commits = []
 
         while commits_url is not None:
             # Get the next page of commits
-            response = requests.get(commits_url, headers=headers)
+            response = requests.get(commits_url, headers=headers, params=params)
             raw_commits = response.json()
 
             # Wait for rate limit reset if needed