Bump ujson from 4.0.2 to 5.1.0 in /docs/pr-analysis

Bumps [ujson](https://github.com/ultrajson/ultrajson) from 4.0.2 to 5.1.0.
- [Release notes](https://github.com/ultrajson/ultrajson/releases)
- [Commits](ultrajson/ultrajson@4.0.2...5.1.0)

---
updated-dependencies:
- dependency-name: ujson
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

docs/pr-analysis/requirements.txt

@@ -11,4 +11,4 @@ requests-ftp==0.3.1
 requests-ntlm==1.1.0
 requestsexceptions==1.4.0
 simplejson==3.17.2
-ujson==4.0.2
+ujson==5.1.0