Pin CI from stable to 1.72.1

Enables better detection of regressions in Rust, a few of which 1.72.1 fixes.

.github/actions/build-dependencies/action.yml

@@ -10,7 +10,7 @@ inputs:
   rust-toolchain:
     description: "Rust toolchain to install"
     required: false
-    default: stable
+    default: 1.72.1
 
   rust-components:
     description: "Rust components to install"

.github/workflows/daily-deny.yml

@@ -20,7 +20,7 @@ jobs:
       - name: Install cargo
         uses: dtolnay/rust-toolchain@5cb429dd810e16ff67df78472fa81cf760f4d1c0
         with:
-          toolchain: stable
+          toolchain: 1.72.1
 
       - name: Install cargo deny
         run: cargo install --locked cargo-deny

.github/workflows/lint.yml

@@ -41,7 +41,7 @@ jobs:
       - name: Install cargo
         uses: dtolnay/rust-toolchain@5cb429dd810e16ff67df78472fa81cf760f4d1c0
         with:
-          toolchain: stable
+          toolchain: 1.72.1
 
       - name: Install cargo deny
         run: cargo install --locked cargo-deny