CI: separated MSRV tests

.github/workflows/test.yml

@@ -48,9 +48,6 @@ jobs:
             target: x86_64-pc-windows-msvc
             toolchain: beta
             # Test both windows-gnu and windows-msvc; use beta rust on one
-          - os: ubuntu-latest
-            target: x86_64-unknown-linux-gnu
-            toolchain: 1.51.0 # temporary MSRV of rand_jitter
           - os: ubuntu-latest
             deps: sudo apt-get update ; sudo apt install gcc-multilib
             target: i686-unknown-linux-gnu
@@ -85,6 +82,25 @@ jobs:
           cargo test --target ${{ matrix.target }} --manifest-path rand_xoshiro/Cargo.toml --all-features
           cargo test --target ${{ matrix.target }} --manifest-path rand_jitter/Cargo.toml --all-features
 
+  msrv:
+    name: MSRV for rand_hc / rand_isaac / rand_xorshift / rand_xoshiro
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/[email protected]
+      - run: cd rand_hc && cargo test --all-features
+      - run: cd rand_isaac && cargo test --all-features
+      - run: cd rand_xorshift && cargo test --all-features
+      - run: cd rand_xoshiro && cargo test --all-features
+
+  jitter:
+    name: MSRV for rand_jitter
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/[email protected]
+      - run: cd rand_jitter && cargo test --features std
+
   test-cross:
     runs-on: ubuntu-latest
     strategy: