build(deps): bump requests in /samples/bookinfo/src/productpage (#562)

Bumps [requests](https://github.com/psf/requests) from 2.21.0 to 2.31.0.
- [Release notes](https://github.com/psf/requests/releases)
- [Changelog](https://github.com/psf/requests/blob/main/HISTORY.md)
- [Commits](https://github.com/psf/requests/compare/v2.21.0...v2.31.0)

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

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
diff --git a/samples/bookinfo/src/productpage/requirements.txt b/samples/bookinfo/src/productpage/requirements.txt
index 856ff7c..3309a52 100644
--- a/samples/bookinfo/src/productpage/requirements.txt
+++ b/samples/bookinfo/src/productpage/requirements.txt
@@ -19,7 +19,7 @@
 nose==1.3.7
 opentracing==1.2.2
 opentracing-instrumentation==2.4.3
-requests==2.21.0
+requests==2.31.0
 simplejson==3.16.0
 six==1.12.0
 threadloop==1.0.2