Bump MimeKit from 2.15.1 to 3.4.0

[dependabot]

Bumps MimeKit from 2.15.1 to 3.4.0.

Changelog

Sourced from MimeKit's changelog.

MimeKit 3.4.0 (2022-08-17)

• Introduced a new IPunycode interface and Punycode class allowing developers to override the default implementation that uses .NET's IdnMapping class. (issue #801)
• Added HtmlAttributeCollection Contains, IndexOf and TryGetValue methods.
• Dropped .NET5.0 support.
• Changed HtmlToHtml converter to avoid decoding character references. (issue #808)
• Fixed BoundStream to only seek in the base stream if seeking is supported.
• Added a new TextPart.TryDetectEncoding() API. (issue #804)
• Added support for message/feedback-report via a new MessageFeedbackReport class.
• Fixed a potential memory leak.
• When unquoting parameter values, don't convert tabs to spaces. (issue #809)
• Don't call Encoding.RegisterProvider() anymore. Rely on developers doing this themselves in their application startup logic.
• Remove System.Text.Encoding.CodePages dependency for net4x.
• Expose the LineNumber property on MimeMessageBeginEventArgs and MimeEntityBeginEventArgs. (issue #819)

MimeKit 3.3.0 (2022-06-11)

• Added Import() methods for X509Certificate2 for all S/MIME contexts. (issue #784)
• Handle S/MIME sha# as well as sha-# micalg names for improved interop. (issue #790)
• Fixed the MemoryBlockStream.Read() method to handle cases where the length of the stream is longer than int.MaxValue.
• Fixed TnefPart.ConvertToMessage() to promote lone multipart/mixed subparts to become the message body much like it used to work pre-v3.2.0. (issue #789)
• Reduced memory usage when using SecureMimeContext.Compress() and CompressAsync().
• Dropped support for net452 and net461 now that their life cycles have ended and are no longer supported by Microsoft. (issue #768)
• Added support for net462.

Special thanks to Fedir Klymenko for his improvements to MemoryBlockStream and SecureMimeContext.Compress!

MimeKit 3.2.0 (2022-03-26)

• Rewrote QuotedPrintableEncoder to more strictly fold at the specified line length. (issue #781)
• Change the default maxLineLength for quoted-printable/base64 encoders to 76 to match the recommendation in the specification (was previously 72).
• Use cached Task instances (e.g. Task.CompletedTask) when possible to improve performance.
• Make use of ReadOnlySpan<T> instead of String.Substring() wherever possible to improve performance.
• Reduced string allocations in other ways.
• Provide MailboxAddress accessors for LocalPart and Domain. (issue #766)

... (truncated)

Commits

• 3016e82 Bumped version to 3.4.0
• 952c1cd Bump Microsoft.NET.Test.Sdk from 17.2.0 to 17.3.0
• 9a454f0 Update FAQ.md
• 5a84169 Remove the System.Text.Encoding.CodePages dependency from the .csproj files
• e05fdf9 Remove System.Text.Encoding.CodePages dependency for net4x
• ebbd551 Expose the LineNumber property on MimeMessageBeginEventArgs and MimeEntityBeg...
• 53424bc Cleanup of nuget PackageReferences
• 1d4d96a Updated unit tests to match charset names case insensitively
• 926827d Bump System.* nuget dependencies to the latest versions
• 64efcd3 Don't call Encoding.RegisterProvider() anymore
• Additional commits viewable in compare view

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[dependabot]

Superseded by #128.