chore(IDX): remove clippy sysroot workaround

This removes a workaround that was necessary in the past to work around
an issue in clippy. The issue is now fixed in clippy, and our clippy
version is recent enough to include the fix.

See also:
* bazelbuild/rules_rust#2277
* rust-lang/rust-clippy#12203

Author: nmattia

.bazelrc

@@ -15,10 +15,6 @@ build:fmt --aspects=@rules_rust//rust:defs.bzl%rustfmt_aspect
 build:fmt --output_groups=+rustfmt_checks
 build --@rules_rust//:rustfmt.toml=//:rustfmt.toml
 
-# https://github.com/bazelbuild/rules_rust/pull/2277 breaks our build in CI
-# TODO(levsha): localise the problem and report to the upstream
-build --@rules_rust//rust/settings:experimental_toolchain_generated_sysroot=False
-
 build:ci --progress_report_interval=30
 
 # Use hermetic JDK