Bump MailKit from 2.15.0 to 3.4.0

[dependabot]

Bumps MailKit from 2.15.0 to 3.4.0.

Changelog

Sourced from MailKit's changelog.

MailKit 3.4.0 (2022-09-05)

• Fixed a bug that caused ImapFolder.Fetch/FetchAsync to throw TaskCanceledException instead of allowing the correct exception to bubble up. (issue #1415)
• Simplified socket connection logic to allow Socket.Connect() to do DNS lookups for us.
• Updated common mail server SSL certificates.
• Dropped net5.0 support.

MailKit 3.3.0 (2022-06-11)

• Added work-around for IMAP BODYSTRUCTURE responses that have a NIL multipart body. (issue #1393)
• Considerably reduced memory overhead from compiler-generated async/await Tasks allocations in the IMAP implementation (mostly focused on FETCH commands/responses). (issue #1335)
• Optimized FETCH response processing for the common case where FETCH responses are returned in sorted order.
• Fixed the IMAP Literal string reader to use UTF-8 with fallback to iso-8859-1 (previously just used iso-8859-1).
• Modified the IMAP ENVELOPE parser to combine ENVELOPE mailbox tokens if there are more than 4. (issue #1369)
• Prevent TypeLoadExceptions in the SmtpClient static .ctor by catching NotSupportedExceptions thrown by IPGlobalProperties.GetIPGlobalProperties() on platforms like WASM. (issue #1381)
• Updated Google, GMX, and Yahoo! Mail SSL certificates.
• Dropped support for net452 and net461.
• Added support for net462.

MailKit 3.2.0 (2022-03-26)

• Do not use ApplicationProtocols with SSL. (issue #1352)
• Updated GMail, Yahoo, and Outlook.com certificates.
• Lazy-initialize MessageSummary.Keywords. This reduces memory usage when the client isn't requesting Flags/Keywords.
• Hard-cache some IMAP FETCH-related tokens in order to relieve GC pressure for commands like FETCH where there can be a LOT of responses containing the same tokens over and over again.
• Converted some IMAP async Task methods to use ValueTask to reduce GC pressure.
• Reduced string allocations in the IMAP logic by avoiding use of ToUpperInvariant().
• Added non-async implementations for ImapStream APIs to be used by the synchronous public APIs to avoid some async overhead.
• Reduce MemoryStream (and thus byte[]) allocations by using a new ByteArrayBuilder.
• Rewrote the IMAP CAPABILITY parser to avoid allocating strings.
• Fixed some cases where IMAP NIL tokens were not compared case insensitively.
• Always include the VERSION block in NTLM messages. (issue #1340)
• Target .NET Framework v4.6.1 instead of v4.6 to match the changes in MimeKit.
• Capture the Socket timeout value in Read/WriteAsync() to have it in case of exceptions. (issue #1327)

MailKit 3.1.1 (2022-01-30)

• Reduced string allocations in Pop3Engine's capability parser.
• Updated GMail and Outlook.com SSL certificates.
• Modified SmtpClient to try and use the system hostname in EHLO/HELO commands. (issue #1314)

... (truncated)

Commits

• c327237 Bumped version to 3.4.0
• 9583cea Updated GMail SSL certificates
• 8f85418 Added unit test for issue #1415
• ddd42c0 Upgrade ImapIdle to new csproj
• 79a416c Updated SSL certificates
• 1a6418c bumped MimeKit to 3.4.0
• 6a9963a Bump Microsoft.NET.Test.Sdk from 17.2.0 to 17.3.0
• 509bb56 Avoid using ContinueWith in the ImapFolder.FetchSummaryItemsAsync handler
• ae36c45 Update FAQ.md
• f2a6bd5 Update FAQ.md
• Additional commits viewable in compare view

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[dependabot]

Superseded by #42.