Bump numpy from 1.19.2 to 1.21.0 in /notebook_sandbox/jwst_boxcar

Bumps [numpy](https://github.com/numpy/numpy) from 1.19.2 to 1.21.0.
- [Release notes](https://github.com/numpy/numpy/releases)
- [Changelog](https://github.com/numpy/numpy/blob/main/doc/HOWTO_RELEASE.rst.txt)
- [Commits](numpy/numpy@v1.19.2...v1.21.0)

---
updated-dependencies:
- dependency-name: numpy
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

notebook_sandbox/jwst_boxcar/requirements.txt

@@ -1,6 +1,6 @@
 notebook==6.1.5
 jupyter_client==5.3.5
-numpy==1.19.2
+numpy==1.21.0
 scipy #==1.5.2
 specutils==1.1.1
 glue-astronomy==0.1