Use the in-tree compiler-builtins

Many of `std`'s dependency have a dependency on the crates.io
`compiler-builtins` when used with the feature
`rustc-std-workspace-core`. Use a Cargo patch to select the in-tree
version instead.

`compiler-builtins` is also added as a dependency of
`rustc-std-workspace-core` so these crates can remove their crates.io
dependency in the future.

Author: tgross35

compiler-builtins/Cargo.toml

@@ -17,9 +17,7 @@ doctest = false
 test = false
 
 [dependencies]
-# For more information on this dependency see
-# https://github.com/rust-lang/rust/tree/master/library/rustc-std-workspace-core
-core = { version = "1.0.1", optional = true, package = "rustc-std-workspace-core" }
+core = { path = "../../core", optional = true }
 
 [build-dependencies]
 cc = { optional = true, version = "1.2" }