Bump scipy from 1.5.2 to 1.5.3 (AtsushiSakai#424)

Bumps [scipy](https://github.com/scipy/scipy) from 1.5.2 to 1.5.3.
- [Release notes](https://github.com/scipy/scipy/releases)
- [Commits](scipy/scipy@v1.5.2...v1.5.3)

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

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

Author: dependabot[bot]

requirements.txt

@@ -1,5 +1,5 @@
 numpy == 1.19.2
-scipy == 1.5.2
+scipy == 1.5.3
 pandas == 1.1.3
 matplotlib == 3.3.2
 cvxpy == 1.1.6