fix: exclude empty wallets and don't show success message when canceling a save file dialog

[brenopolanski]

Summary

Fixes #1890 #1891.

Checklist

• Documentation (if necessary)
• Tests (if necessary)
• Ready to be merged

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (develop@5ebf236). Click here to learn what that means.
The diff coverage is 20.00%.

@@            Coverage Diff             @@
##             develop    #1892   +/-   ##
==========================================
  Coverage           ?   58.86%           
==========================================
  Files              ?      371           
  Lines              ?     9307           
  Branches           ?     1921           
==========================================
  Hits               ?     5479           
  Misses             ?     3602           
  Partials           ?      226           

Impacted Files	Coverage Δ
...c/renderer/components/Modal/ModalExportWallets.vue	33.84% <20.00%> (ø)
...derer/components/Network/NetworkSelectionModal.vue	16.66% <0.00%> (ø)
src/renderer/workers/bip38-worker.js	0.00% <0.00%> (ø)
...er/services/crypto/business-resignation.builder.js	100.00% <0.00%> (ø)
...rer/services/crypto/transaction-builder.service.js	100.00% <0.00%> (ø)
...erer/store/migrations/2.2.0 - initial migration.js	100.00% <0.00%> (ø)
...r/services/crypto/delegate-registration.builder.js	100.00% <0.00%> (ø)
...Manager/PluginManagerModals/PluginInstallModal.vue	87.50% <0.00%> (ø)
...vices/plugin-manager/sandbox/big-number-sandbox.js	25.00% <0.00%> (ø)
...renderer/components/Contact/ContactRenameModal.vue	25.00% <0.00%> (ø)
... and 362 more

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