Bump MailKit from 2.15.0 to 3.1.1

[dependabot]

Bumps MailKit from 2.15.0 to 3.1.1.

Changelog

Sourced from MailKit's changelog.

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)

MailKit 3.1.0 (2022-01-14)

• Fixed NTLM to always prefer the supplied domain over the TargetName or TargetInfo.DomainName. (issue #582)
• Updated GMail and Outlook.com SSL certificate info.
• Added a new SslCipherSuite property to each client that allows developers to get information about the SSL/TLS cipher suite that was negotiated with the server. (pull #1312)
• Reduced string allocations in SmtpClient's EHLO capability parsing logic.
• Default ProtocolLogger.RedactSecrets to true for added added security.
• Added work-around for parsing malformed GMail ENVELOPE responses that reverse the name and address components of the Sender address. (pull #1319)
• Added net6.0 to the list of TargetFrameworks.

MailKit 3.0.0 (2021-12-11)

• Removed APIs marked as [Obsolete] in 2.x.
• Simplify Fetch()/FetchAsync() APIs by using a new IFetchRequest parameter instead. Made previous APIs into extension methods to aid in porting from 2.x.
• Replaced Add/Remove/SetFlags() APIs with Store()/StoreAsync() and simplified the APIs by using a new IStoreFlagsRequest parameter. Made previous APIs into extension methods to aid in porting from 2.x.
• Replaced Add/Remove/SetLabels() APIs with Store()/StoreAsync() and simplified the APIs by using a new IStoreLabelsRequest parameter. Made previous APIs into extension methods to aid in porting from 2.x.
• Simplify Append()/AppendAsync() APIs by using a new IAppendRequest parameter instead. Made previous APIs into extension methods to aid in porting from 2.x.
• Simplify Replace()/ReplaceAsync() APIs by using a new IReplaceRequest parameterinstead. Made previous APIs into extension methods to aid in porting from 2.x.
• Updated SmtpClient.Send()/SendAsync() methods to return a string. (issue #1161)
• Added support for the SCRAM-SHA*-PLUS SASL mechanisms. (issue #950)
• Added authzid support for SCRAM SASL mechanisms.
• Added support for the ANONYMOUS SASL mechanism.
• Added support for an HttpsProxyClient. (issue #1251)
• Added AcceptedKeywords and PermanentKeywords to IMailFolder. (issue #1256)
• Rewrote NTLM support based on official specs. Now supports channel-binding and using the default system credentials.
• Modified ImapFolder.Fetch(int, int, ...) to shortcut if ImapFolder.Count == 0.
• Updated SmtpClient to append an ORCPT arg to RCPT TO commands and to hex-encode the ENVID parameter value.
• Improved/simplified logic for ranking SASL authentication mechisms for each client.
• Added SaslMechanism.ChallengeAsync() to facilitate future SASL mechanisms that may need to make network requests such as Kerberos/GSSAPI and perhaps even future/custom OAuth2 implementations.
• Always set SearchResults.Count/Min/Max properties if we can.

... (truncated)

Commits

• 7f3affd Bumped version to 3.1.1
• f6f4a4e Updated README.md
• 839ec61 Updated README.md
• 8c50d12 Updated GettingStarted.md
• a7db8cf Bump NUnit3TestAdapter from 4.2.0 to 4.2.1 (#1323)
• a5637f9 minor update to previous unit test
• 163fa9b Added unit tests for SmtpClient.OnNoRecipientsAccepted()
• dfafce8 Added more SmtpClient unit tests
• 5c5e11d Reduce string allocations in Pop3Engine's capability parser
• a818ada Updated GMail SSL certificates
• Additional commits viewable in compare view

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[dependabot]

Superseded by #46.