[deps] DevOps: Update mcr.microsoft.com/devcontainers/dotnet Docker tag to v9

[renovate[bot]]

This PR contains the following updates:

Package	Update	Change
mcr.microsoft.com/devcontainers/dotnet	major	8.0 -> 9.0

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Configuration

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[bitwarden-bot]

Internal tracking:

• ID: PM-12953
• Link: https://bitwarden.atlassian.net/browse/PM-12953

[codecov[bot]]

Codecov Report

:white_check_mark: All modified and coverable lines are covered by tests. :white_check_mark: Project coverage is 42.58%. Comparing base (702a81b) to head (c5c91af). :warning: Report is 1091 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #4832   +/-   ##
=======================================
  Coverage   42.58%   42.58%           
=======================================
  Files        1406     1406           
  Lines       65074    65074           
  Branches     5962     5962           
=======================================
  Hits        27715    27715           
  Misses      36131    36131           
  Partials     1228     1228           

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[audreyality]

Related: #4781