Bump pyyaml from 5.3 to 5.4 in /stackl/cli

Bumps [pyyaml](https://github.com/yaml/pyyaml) from 5.3 to 5.4.
- [Release notes](https://github.com/yaml/pyyaml/releases)
- [Changelog](https://github.com/yaml/pyyaml/blob/master/CHANGES)
- [Commits](yaml/pyyaml@5.3...5.4)

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

Author: dependabot[bot]

stackl/cli/setup.py

@@ -8,7 +8,7 @@
     py_modules=['stackl', 'commands', 'context'],
     packages=find_packages(),
     install_requires=[
-        f'stackl-client==0.3.4dev', 'pyYAML==5.3', 'Click==7.0',
+        f'stackl-client==0.3.4dev', 'pyYAML==5.4', 'Click==7.0',
         'mergedeep==1.3.0', 'tabulate==0.8.6', 'glom==19.10.0'
     ],
     entry_points='''