Bump cvxpy from 1.1.4 to 1.1.5 (AtsushiSakai#389)

Bumps [cvxpy](https://github.com/cvxgrp/cvxpy) from 1.1.4 to 1.1.5.
- [Release notes](https://github.com/cvxgrp/cvxpy/releases)
- [Changelog](https://github.com/cvxgrp/cvxpy/blob/master/CHANGELOG.md)
- [Commits](cvxgrp/cvxpy@v1.1.4...v1.1.5)

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

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

Author: dependabot[bot]

requirements.txt

@@ -2,4 +2,4 @@ numpy == 1.19.1
 scipy == 1.5.2
 pandas == 1.1.1
 matplotlib == 3.3.1
-cvxpy == 1.1.4
+cvxpy == 1.1.5