add setter for parsers

[khillion]

Description

This PR follows minor modifications while exploring metadata for InSPIRe project.

Changelogs

• Add setter for dataframe property for parsers

Definition of Done

• [x] ~New code is tested with unit tests~
• [x] ~Documentation has been updated~
• [ ] Pull Request has been revised by a maintainer of the project

[codecov-commenter]

Codecov Report

Merging #76 (b0d6f59) into master (d48d525) will increase coverage by 1.38%. The diff coverage is 66.66%.

@@            Coverage Diff             @@
##           master      #76      +/-   ##
==========================================
+ Coverage   57.94%   59.32%   +1.38%     
==========================================
  Files          60       60              
  Lines        2423     2503      +80     
==========================================
+ Hits         1404     1485      +81     
+ Misses       1019     1018       -1     

Flag	Coverage Δ
unittests	59.32% <66.66%> (+1.38%)	:arrow_up:

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
moonstone/parsers/base.py	76.66% <66.66%> (-1.12%)	:arrow_down:
moonstone/analysis/diversity/alpha.py	97.91% <0.00%> (+1.25%)	:arrow_up:
moonstone/analysis/statistical_test.py	95.32% <0.00%> (+3.38%)	:arrow_up:
moonstone/analysis/diversity/beta.py	74.35% <0.00%> (+4.66%)	:arrow_up:

---

Continue to review full report at Codecov.

Legend - Click here to learn more Δ = absolute <relative> (impact), ø = not affected, ? = missing data Powered by Codecov. Last update d48d525...b0d6f59. Read the comment docs.