chore(deps): bump pyinstaller from 6.18.0 to 6.19.0 in /requirements (aws#8672)

Bumps [pyinstaller](https://github.com/pyinstaller/pyinstaller) from 6.18.0 to 6.19.0.
- [Release notes](https://github.com/pyinstaller/pyinstaller/releases)
- [Changelog](https://github.com/pyinstaller/pyinstaller/blob/develop/doc/CHANGES.rst)
- [Commits](pyinstaller/pyinstaller@v6.18.0...v6.19.0)

---
updated-dependencies:
- dependency-name: pyinstaller
  dependency-version: 6.19.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

requirements/pyinstaller-build.txt

@@ -1,3 +1,3 @@
 # Executable binary builder requirements
 setuptools==80.9.0
-pyinstaller==6.18.0
+pyinstaller==6.19.0