feat: Use application/octet-stream as a fallback media type to avoid "Unknown media type" errors

[matheusbsilva137]

Proposed changes (including videos or screenshots)

• Allow any file with an unknown media type (the ones not defined in IANA, Apache or nginx MIME types will be classified as application/octet-stream as default if the new setting is disabled) to be uploaded by using a application/octet-stream as the default/fallback MIME type;
• Normalize how MIME types are identified throughout the application (by using the mime package in the back-end too)
• Add alert to "Blocked Media Types" setting
  

Issue(s)

Steps to test or reproduce

Access a room and try uploading a drawio file in it (such as the one available in the end-to-end tests added by this PR); Expected behavior: The file should be accepted and uploaded succesfully. Check the rocketchat_uploads DB collection to confirm the file has been uploaded with the application/octet-stream media type (default one for unknown media extensions);
Current behavior: the file isn't accepted and an "Unknown media type not accepted" error is thrown.

Further comments

SUP-531

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[changeset-bot]

🦋 Changeset detected

Latest commit: 2886ac3

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

This PR includes changesets to release 34 packages

Name	Type
@rocket.chat/meteor	Minor
@rocket.chat/i18n	Minor
@rocket.chat/mock-providers	Patch
@rocket.chat/ui-contexts	Major
@rocket.chat/web-ui-registration	Major
@rocket.chat/fuselage-ui-kit	Major
@rocket.chat/ui-client	Major
@rocket.chat/gazzodown	Major
@rocket.chat/livechat	Patch
@rocket.chat/ui-avatar	Major
@rocket.chat/ui-video-conf	Major
@rocket.chat/uikit-playground	Patch
@rocket.chat/ddp-streamer	Patch
@rocket.chat/omnichannel-transcript	Patch
@rocket.chat/core-typings	Minor
@rocket.chat/rest-typings	Minor
@rocket.chat/apps	Patch
@rocket.chat/core-services	Patch
@rocket.chat/cron	Patch
@rocket.chat/model-typings	Patch
@rocket.chat/account-service	Patch
@rocket.chat/authorization-service	Patch
@rocket.chat/presence-service	Patch
@rocket.chat/queue-worker	Patch
@rocket.chat/stream-hub-service	Patch
@rocket.chat/api-client	Patch
@rocket.chat/license	Patch
@rocket.chat/omnichannel-services	Patch
@rocket.chat/pdf-worker	Patch
@rocket.chat/presence	Patch
rocketchat-services	Patch
@rocket.chat/ddp-client	Patch
@rocket.chat/models	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 55.06%. Comparing base (3039968) to head (2886ac3).

Additional details and impacted files

@@             Coverage Diff             @@
##           develop   #32471      +/-   ##
===========================================
- Coverage    56.53%   55.06%   -1.47%     
===========================================
  Files         2484     2397      -87     
  Lines        54693    53207    -1486     
  Branches     11286    10946     -340     
===========================================
- Hits         30921    29300    -1621     
- Misses       21122    21319     +197     
+ Partials      2650     2588      -62     

Flag	Coverage Δ
e2e	53.36% <100.00%> (-2.80%)	⬇️
unit	72.16% <50.00%> (+<0.01%)	⬆️

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[MarcosSpessatto]

Let's rewrite the description please, we are mentioning Reject unknown media types, but the name/description for the setting is completely different (which is good in my opinion)