fix: empty "Apps_Error_" toast message when private app installation fails

[pierre-lehnen-rc]

Proposed changes (including videos or screenshots)

Issue(s)

CORE-985

Steps to test or reproduce

Empty error would show up if RC failed to store the app file to disk or if it failed to create an user for the app.

Should be reproduceable by configuring an invalid storage for the apps

Further comments

[dionisio-bot]

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[changeset-bot]

🦋 Changeset detected

Latest commit: 0a38958

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 37 packages

Name	Type
@rocket.chat/i18n	Patch
@rocket.chat/meteor	Patch
@rocket.chat/mock-providers	Patch
@rocket.chat/ui-contexts	Patch
@rocket.chat/web-ui-registration	Patch
@rocket.chat/fuselage-ui-kit	Patch
@rocket.chat/ui-client	Patch
@rocket.chat/ui-voip	Patch
@rocket.chat/uikit-playground	Patch
@rocket.chat/gazzodown	Patch
@rocket.chat/livechat	Patch
@rocket.chat/ui-avatar	Patch
@rocket.chat/ui-video-conf	Patch
@rocket.chat/core-typings	Patch
@rocket.chat/rest-typings	Patch
@rocket.chat/api-client	Patch
@rocket.chat/apps	Patch
@rocket.chat/core-services	Patch
@rocket.chat/cron	Patch
@rocket.chat/ddp-client	Patch
@rocket.chat/freeswitch	Patch
@rocket.chat/model-typings	Patch
@rocket.chat/account-service	Patch
@rocket.chat/authorization-service	Patch
@rocket.chat/ddp-streamer	Patch
@rocket.chat/omnichannel-transcript	Patch
@rocket.chat/presence-service	Patch
@rocket.chat/queue-worker	Patch
@rocket.chat/stream-hub-service	Patch
@rocket.chat/license	Patch
@rocket.chat/omnichannel-services	Patch
@rocket.chat/pdf-worker	Patch
@rocket.chat/presence	Patch
rocketchat-services	Patch
@rocket.chat/models	Patch
@rocket.chat/network-broker	Patch
@rocket.chat/instance-status	Patch

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 59.31%. Comparing base (091cff3) to head (0a38958).
Report is 2 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop   #35189   +/-   ##
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  Coverage    59.31%   59.31%           
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  Files         2825     2825           
  Lines        68158    68158           
  Branches     15123    15123           
========================================
  Hits         40430    40430           
  Misses       24900    24900           
  Partials      2828     2828           

Flag	Coverage Δ
unit	75.33% <ø> (ø)

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