Replace no_std with std feature in gitlab actions config

Author: jhbruhn

.github/workflows/build.yml

@@ -14,7 +14,7 @@ jobs:
     strategy:
       matrix:
         rust: [stable]
-        FEATURES: ['', 'from_str', 'no_std']
+        FEATURES: ['', 'from_str', 'std']
 
         include:
           # Test nightly but don't fail
@@ -62,7 +62,7 @@ jobs:
       - uses: actions-rs/cargo@v1
         with:
           command: build
-          args: --target=${{ matrix.TARGET }} --features no_std
+          args: --target=${{ matrix.TARGET }}
 
   fmt:
     runs-on: ubuntu-latest
@@ -83,7 +83,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        FEATURES: ['', 'from_str', 'no_std']
+        FEATURES: ['', 'from_str', 'std']
     steps:
       - uses: actions/checkout@v2
       - uses: actions-rs/toolchain@v1