rust-toolchain: use christmas nightly

Stan Drozd · Stan Drozd · commit d77ae09f814e · 2023-01-03T18:26:06.000+01:00
diff --git a/rust-toolchain b/rust-toolchain
@@ -2,5 +2,5 @@
 # ci/rust-version.sh in the branch of the solana repo that corresponds
 # with the version we're using.
 [toolchain]
-channel = "1.63.0"
+channel = "nightly-2022-02-24"
 profile = "minimal"
