deps: bump requests to 2.33.0

[katsugtgz]

Updates requests to 2.33.0 to clear the advisories reported for the pinned 2.32.3. This goes further than the open dependabot PR #148 (2.32.4), which still sits inside both affected ranges.

Evidence:

• requirements.txt pinned requests==2.32.3
• osv-scanner reported PYSEC-2026-1872 (GHSA-9hjg-9r4m-mvj7) and PYSEC-2026-2275 (GHSA-gc5v-m9x4-r6x2) for requests 2.32.3
• updated version: 2.33.0

Validation:

• osv-scanner no longer reports those advisories for requests 2.33.0
• pip check passes with requests 2.33.0 and the repo's other pins
• the full pip install -r requirements.txt fails on this machine at systemd-python (needs libsystemd-dev, an OS package), before and after this change; that failure is unrelated to requests

Scope: requirements.txt only.