Please release v2.9.1 with the fixes in main branch

[x448]

These updates from last weekend and this weekend seem enough for a new patch release.

• Reject encoding nil inside CBOR indefinite-length string #750
• Refactor and add tests #752
• Small bugfixes, defensive checks, and improvements #753
• Refactor parseMapToStruct(), getDecodingStructType(), getEncodingStructType(), and field struct #754

[fxamacker]

@x448 Yeah, it has been fuzzing and I will release tag either tonight or tomorrow morning.

I need another PR (not opened yet) reviewed tonight or early morning before tagging the release.

[fxamacker]

Tagged v2.9.1 with additional fixes (related to keyasint feature) that were being fuzz tested:

• Fix several issues related to keyasint tag option #757

fyi: @benluddy @liggitt @qmuntal @thomas-fossati