Bump MSRV to 1.81 in inout CI

Author: newpavlov

.github/workflows/inout.yml

@@ -25,7 +25,7 @@ jobs:
     strategy:
       matrix:
         rust:
-          - 1.65.0 # MSRV
+          - 1.81.0 # MSRV
           - stable
         target:
           - thumbv7em-none-eabi
@@ -50,7 +50,7 @@ jobs:
     strategy:
       matrix:
         rust:
-          - 1.65.0 # MSRV
+          - 1.81.0 # MSRV
           - stable
     steps:
       - uses: actions/checkout@v4