Remove impl const and ~const in the standard library

Otherwise it will fail to compile on nightly-2023-04-19

See rust-lang/rust#110395

Author: equation314

src/base.rs

@@ -174,7 +174,7 @@ impl<G: BaseGuard, T: ?Sized> BaseSpinLock<G, T> {
     }
 }
 
-impl<G: BaseGuard, T: ?Sized + ~const Default> const Default for BaseSpinLock<G, T> {
+impl<G: BaseGuard, T: ?Sized + Default> Default for BaseSpinLock<G, T> {
     #[inline(always)]
     fn default() -> Self {
         Self::new(Default::default())

src/lib.rs

@@ -9,7 +9,6 @@
 //!   in use. By default, this feature is disabled.
 
 #![cfg_attr(not(test), no_std)]
-#![feature(const_trait_impl)]
 
 mod base;