Bump cvxpy from 1.1.17 to 1.1.18 (AtsushiSakai#615)

Bumps [cvxpy](https://github.com/cvxpy/cvxpy) from 1.1.17 to 1.1.18.
- [Release notes](https://github.com/cvxpy/cvxpy/releases)
- [Changelog](https://github.com/cvxpy/cvxpy/blob/master/CHANGELOG.md)
- [Commits](cvxpy/cvxpy@v1.1.17...v1.1.18)

---
updated-dependencies:
- dependency-name: cvxpy
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

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

Author: dependabot[bot]

requirements.txt

@@ -2,7 +2,7 @@ numpy == 1.22.0
 scipy == 1.7.3
 pandas == 1.3.5
 matplotlib == 3.5.1
-cvxpy == 1.1.17
+cvxpy == 1.1.18
 pytest == 6.2.5 # For unit test
 pytest-xdist == 2.5.0 # For unit test
 sphinx == 4.3.2 # For sphinx documentation