add msrv to env to prevent so much duplication

Author: brxken128

.github/workflows/zeroize.yml

@@ -7,7 +7,7 @@ on:
       - "zeroize/**"
       - "Cargo.*"
   push:
-    branches: master
+    branches: [master]
 
 permissions:
   contents: read
@@ -19,14 +19,15 @@ defaults:
 env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
+  MSRV: 1.61.0
 
 jobs:
   build:
     runs-on: ubuntu-latest
     strategy:
       matrix:
         rust:
-          - 1.61.0 # MSRV
+          - ${{ MSRV }}
           - stable
         target:
           - armv7a-none-eabi
@@ -53,7 +54,7 @@ jobs:
           # 32-bit Linux
           - target: i686-unknown-linux-gnu
             platform: ubuntu-latest
-            rust: 1.61.0 # MSRV
+            rust: ${{ MSRV }}
             deps: sudo apt update && sudo apt install gcc-multilib
           - target: i686-unknown-linux-gnu
             platform: ubuntu-latest
@@ -63,23 +64,23 @@ jobs:
           # 64-bit Linux
           - target: x86_64-unknown-linux-gnu
             platform: ubuntu-latest
-            rust: 1.61.0 # MSRV
+            rust: ${{ MSRV }}
           - target: x86_64-unknown-linux-gnu
             platform: ubuntu-latest
             rust: stable
 
           # 64-bit macOS x86_64
           - target: x86_64-apple-darwin
             platform: macos-latest
-            rust: 1.61.0 # MSRV
+            rust: ${{ MSRV }}
           - target: x86_64-apple-darwin
             platform: macos-latest
             rust: stable
 
           # 64-bit Windows
           - target: x86_64-pc-windows-msvc
             platform: windows-latest
-            rust: 1.61.0 # MSRV
+            rust: ${{ MSRV }}
           - target: x86_64-pc-windows-msvc
             platform: windows-latest
             rust: stable
@@ -102,7 +103,7 @@ jobs:
         include:
           # PPC32
           - target: powerpc-unknown-linux-gnu
-            rust: 1.61.0 # MSRV
+            rust: ${{ MSRV }}
           - target: powerpc-unknown-linux-gnu
             rust: stable
     runs-on: ubuntu-latest
@@ -121,7 +122,7 @@ jobs:
       matrix:
         include:
           - target: aarch64-unknown-linux-gnu
-            rust: 1.61.0
+            rust: ${{ MSRV }}
           - target: aarch64-unknown-linux-gnu
             rust: stable
     runs-on: ubuntu-latest