Bump MSRV to 1.73.0.

Author: khuey

.github/workflows/main.yml

@@ -265,7 +265,7 @@ jobs:
         with:
           submodules: true
       - name: Install Rust
-        run: rustup update 1.65.0 --no-self-update && rustup default 1.65.0
+        run: rustup update 1.73.0 --no-self-update && rustup default 1.73.0
       - run: cargo build
 
   miri:

Cargo.toml

@@ -14,7 +14,7 @@ autoexamples = true
 autotests = true
 edition = "2021"
 exclude = ["/ci/"]
-rust-version = "1.65.0"
+rust-version = "1.73.0"
 
 [workspace]
 members = ['crates/cpp_smoke_test', 'crates/as-if-std']