Bugfix: Standard keywords in make_test_df()

[Magnus167]

The function used start_date and end_date to specify dates, whereas the rest of the package uses start and end (with the notable exception of ms.download)

[codecov]

Codecov Report

Merging #1014 (64927df) into develop (889d546) will not change coverage.
Report is 1 commits behind head on develop.
The diff coverage is 100.00%.

❗ Current head 64927df differs from pull request most recent head 324f949. Consider uploading reports for the commit 324f949 to get more accurate results

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #1014   +/-   ##
========================================
  Coverage    63.70%   63.70%           
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  Files           45       45           
  Lines         4987     4987           
========================================
  Hits          3177     3177           
  Misses        1810     1810           

Files	Coverage Δ
...rosynergy/management/simulate_quantamental_data.py	87.24% <100.00%> (ø)
macrosynergy/panel/linear_composite.py	94.11% <ø> (ø)
macrosynergy/visuals/view.py	57.77% <ø> (ø)