Bump actions-rs/toolchain from 1 to 1.0.7

Bumps [actions-rs/toolchain](https://github.com/actions-rs/toolchain) from 1 to 1.0.7.
- [Release notes](https://github.com/actions-rs/toolchain/releases)
- [Changelog](https://github.com/actions-rs/toolchain/blob/master/CHANGELOG.md)
- [Commits](https://github.com/actions-rs/toolchain/compare/v1...v1.0.7)

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/coverage.yaml

@@ -17,7 +17,7 @@ jobs:
     steps:
       - uses: actions/checkout@v2.3.4
 
-      - uses: actions-rs/toolchain@v1
+      - uses: actions-rs/toolchain@v1.0.7
         with:
           toolchain: nightly
           override: true

.github/workflows/main.yml

@@ -10,7 +10,7 @@ jobs:
     - uses: actions/checkout@v2.3.4
     # Because we use nightly features for building docs,
     # using --all-features will fail without nightly toolchain.
-    - uses: actions-rs/toolchain@v1
+    - uses: actions-rs/toolchain@v1.0.7
       with:
         toolchain: nightly
         override: true