fix: avoid problematic serde release serde 1.0.172 and up rely on opaque non-reproducible binary blobs to function, explicitly not providing a library-level opt-out. This is problematic for two reasons: - directly, unauditable binary blobs are a security issue. - indirectly, it becomes much harder to predict future behaviors of the crate. As such, I am willing to go on a limb here and forbid building rust-analyzer with those versions of serde. Normally, my philosophy is to defer the choice to the end user, but it's also a design constraint of rust-analyzer that we don't run random binaries downloaded from the internet without explicit user's concent. Concretely, this upper-bounds serde for both rust-analyzer workspace, as well as the lsp-server lib. See https://github.com/serde-rs/serde/issues/2538 for wider context.