Rollup merge of rust-lang#93592 - est31:remove_unused_deps, r=bjorn3

Remove unused dep from rustc_arena

Author: matthiaskrgr

Cargo.lock

@@ -3403,7 +3403,6 @@ dependencies = [
 name = "rustc_arena"
 version = "0.0.0"
 dependencies = [
- "rustc_data_structures",
  "smallvec",
 ]
 

compiler/rustc_arena/Cargo.toml

@@ -4,5 +4,4 @@ version = "0.0.0"
 edition = "2021"
 
 [dependencies]
-rustc_data_structures = { path = "../rustc_data_structures" }
 smallvec = { version = "1.6.1", features = ["union", "may_dangle"] }