Bump portion from 2.1.3 to 2.1.4 in /python/requirements/CI-complete

Bumps [portion](https://github.com/AlexandreDecan/portion) from 2.1.3 to 2.1.4.
- [Release notes](https://github.com/AlexandreDecan/portion/releases)
- [Changelog](https://github.com/AlexandreDecan/portion/blob/master/CHANGELOG.md)
- [Commits](AlexandreDecan/portion@2.1.3...2.1.4)

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

Author: dependabot-preview[bot]

python/requirements/CI-complete/requirements.txt

@@ -11,7 +11,7 @@ msprime==0.7.4
 networkx==2.5
 newick==1.0.0
 numpy==1.19.4
-portion==2.1.3
+portion==2.1.4
 pyparsing==2.4.7
 pysam==0.16.0.1
 pytest==6.1.2