Fix write disposition

[jdddog]

OpenCitations shouldn't be using append and the main table of Crossref Events can use the default write empy.

[codecov]

Codecov Report

Patch coverage has no change and project coverage change: -0.05 ⚠️

Comparison is base (b7ed3d3) 95.79% compared to head (20a6529) 95.75%.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #170      +/-   ##
===========================================
- Coverage    95.79%   95.75%   -0.05%     
===========================================
  Files           19       19              
  Lines         4642     4642              
  Branches       622      622              
===========================================
- Hits          4447     4445       -2     
- Misses         122      123       +1     
- Partials        73       74       +1     

Impacted Files	Coverage Δ
...y_workflows/workflows/crossref_events_telescope.py	87.82% <ø> (ø)
...ry_workflows/workflows/open_citations_telescope.py	95.90% <ø> (ø)

... and 1 file with indirect coverage changes

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[keegansmith21]

Changes look good. Thanks Jamie!