fix: added toString for CentralErrorMessage

[florian42]

Closes: #821

All tests were executed succesfully.

[codecov-io]

Codecov Report

Merging #822 into master will decrease coverage by <.01%.
The diff coverage is 0%.

@@             Coverage Diff              @@
##             master     #822      +/-   ##
============================================
- Coverage     48.63%   48.63%   -0.01%     
+ Complexity     1643     1642       -1     
============================================
  Files           192      192              
  Lines         10319    10320       +1     
  Branches        743      743              
============================================
  Hits           5019     5019              
- Misses         4942     4943       +1     
  Partials        358      358

Impacted Files	Coverage Δ	Complexity Δ
...it/briefcase/push/central/CentralErrorMessage.java	0% <0%> (ø)	0 <0> (ø)	⬇️
...g/opendatakit/briefcase/ui/export/ExportPanel.java	48.07% <0%> (ø)	14% <0%> (ø)	⬇️

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[ggalmazor]

Looking good. Thanks, @florian42!

[ggalmazor]

So, some tips for testing this copied from the issue:

• Unzip this form into Briefcase's storage directory. (Wrong ZIP)
• Unzip Simple Form.zip into Briefcase's storage directory.
• (Re)Start Briefcase
• Push the form to a Central server

[kkrawczyk123]

Finally tested with success!
Verified on Ubuntu, MacOS and Windows.

@opendatakit-bot unlabel "needs testing"
@opendatakit-bot label "behavior verified"

[ggalmazor]

Thank you for your patience, @kkrawczyk123 ;)