The 1.85 MSRV is inaccurate with all features

[LDeakin]

The 1.85 MSRV is inaccurate with all features

error[E0658]: `let` expressions in this position are unstable
  --> /home/runner/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/object_store-0.14.1/src/client/token.rs:81:12
   |
81 |         if let Some(cache) = self.cache.read().await.as_ref()
   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information

error[E0658]: `let` expressions in this position are unstable
  --> /home/runner/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/object_store-0.14.1/src/client/token.rs:88:12
   |
88 |         if let Some(cache) = guard.as_ref()
   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information

For more information about this error, try `rustc --explain E0658`.
error: could not compile `object_store` (lib) due to 2 previous errors

See https://github.com/zarrs/zarrs_object_store/actions/runs/29831899978/job/88638534711

The CI action that calls cargo-msrv could append --all-features to catch this.

[progval]

For what it's worth, the affected versions are: v0.13.2, v0.14.0, and v0.14.1. v0.13.1 is fine