Set MSRV to 1.91.0; bump version to 2.0.1

[dcherian]

Closes #2050

I changed the workflows too

[li-em]

We need 1.91.1 since aws-sdk-rust needs it

error: rustc 1.91.0 is not supported by the following packages:
  aws-config@1.8.15 requires rustc 1.91.1
  aws-credential-types@1.2.14 requires rustc 1.91.1
  aws-runtime@1.7.2 requires rustc 1.91.1
  aws-sdk-s3@1.127.0 requires rustc 1.91.1
  aws-sdk-sso@1.97.0 requires rustc 1.91.1
  aws-sdk-ssooidc@1.99.0 requires rustc 1.91.1
  aws-sdk-sts@1.101.0 requires rustc 1.91.1
  aws-sigv4@1.4.2 requires rustc 1.91.1
  aws-smithy-async@1.2.14 requires rustc 1.91.1
  aws-smithy-checksums@0.64.6 requires rustc 1.91.1
  aws-smithy-eventstream@0.60.20 requires rustc 1.91.1
  aws-smithy-http@0.63.6 requires rustc 1.91.1
  aws-smithy-http-client@1.1.12 requires rustc 1.91.1
  aws-smithy-json@0.62.5 requires rustc 1.91.1
  aws-smithy-observability@0.2.6 requires rustc 1.91.1
  aws-smithy-query@0.60.15 requires rustc 1.91.1
  aws-smithy-runtime@1.10.3 requires rustc 1.91.1
  aws-smithy-runtime-api@1.11.6 requires rustc 1.91.1
  aws-smithy-types@1.4.7 requires rustc 1.91.1
  aws-smithy-types-convert@0.60.14 requires rustc 1.91.1
  aws-smithy-xml@0.60.15 requires rustc 1.91.1
  aws-types@1.3.14 requires rustc 1.91.1
  aws-types@1.3.14 requires rustc 1.91.1
  aws-types@1.3.14 requires rustc 1.91.1

[mpiannucci]

This might cause issues

[mpiannucci]

But hopefully not