Update MSRV to 1.61. (#284)

Signed-off-by: Josh Matthews <[email protected]>

Author: jdm

.github/workflows/ci.yml

@@ -20,7 +20,7 @@ jobs:
 
     strategy:
       matrix:
-        rust: [1.60.0, nightly, beta, stable]
+        rust: [1.61.0, nightly, beta, stable]
 
     steps:
       - uses: actions/checkout@v2