loosen mime package constraint

[mx1up]

A breaking change is about to be released for the mime package: the return value of extensionFromMime function has become nullable. If there is no extension found for the mime type, null is now returned instead of the mimeType being passed. Or in code:

/// Returns the extension for the given MIME type.
///
/// If there are multiple extensions for [mime], return the first occurrence in
/// the map. If there are no extensions for [mime], return [mime].
String extensionFromMime(String mime) 

became

/// The default file extension for a given MIME type.
///
/// If [mimeType] has multiple associated extensions,
/// the returned string is one of those, chosen as the default
/// extension for that MIME type.
///
/// Returns `null` if [mimeType] is not a recognized and
/// supported MIME type.
String? extensionFromMime(String mimeType)

see dart-lang/tools#431 (comment) for more info.

Since I did not find any usages of this method in this package, we believe it's safe to loosen the constraint here.

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[kevmoo]

Gah! We need to clean up the <> bits first @natebosch

[mx1up]

thanks!

Gah! We need to clean up the <> bits first @natebosch

not sure what you are referring too 🤔

[mx1up]

ok, now I follow :) https://github.com/dart-lang/shelf/actions/runs/10669248449/job/29753231481

[natebosch]

@mx1up this is published now

[mx1up]

@natebosch thank you for the swift service 🙏