Bump ipython from 7.29.0 to 7.30.0 (AtsushiSakai#588)

Bumps [ipython](https://github.com/ipython/ipython) from 7.29.0 to 7.30.0.
- [Release notes](https://github.com/ipython/ipython/releases)
- [Commits](ipython/ipython@7.29.0...7.30.0)

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

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

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

Author: dependabot[bot]

requirements.txt

@@ -7,4 +7,4 @@ pytest == 6.2.5 # For unit test
 pytest-xdist == 2.4.0 # For unit test
 sphinx < 4.0 # For sphinx documentation
 sphinx_rtd_theme == 1.0.0
-IPython == 7.29.0 # For sphinx documentation
+IPython == 7.30.0 # For sphinx documentation