Fix publish (EmbarkStudios#6)

* Fix publish workflow
* Improve workflow link, top level desc

.github/workflows/publish.yaml

@@ -9,9 +9,6 @@ jobs:
     runs-on: ubuntu-latest
     if: startsWith(github.ref, 'refs/tags/')
     steps:
-    - name: Publish to crates.io
-      env:
-        CRATES_IO_TOKEN: ${{ secrets.CRATES_IO_TOKEN }}
     - uses: actions/checkout@v1
     - uses: actions-rs/toolchain@v1
       with:
@@ -31,5 +28,7 @@ jobs:
         command: test
     - name: cargo publish
       uses: actions-rs/cargo@v1
+      env:
+        CRATES_IO_TOKEN: ${{ secrets.CRATES_IO_TOKEN }}
       with:
         command: publish

.mergify.yml

@@ -5,7 +5,6 @@ pull_request_rules:
       - "#review-requested=0"
       - "#changes-requested-reviews-by=0"
       - "#commented-reviews-by=0"
-      - status-success=Travis CI - Pull Request
       - base=master
       - label!=work-in-progress
     actions:

README.md

@@ -1,12 +1,12 @@
 # 🆔 spdx
 
-[![Build Status](https://github.com/EmbarkStudios/spdx/workflows/CI/badge.svg)](https://github.com/EmbarkStudios/spdx/actions)
+[![Build Status](https://github.com/EmbarkStudios/spdx/workflows/CI/badge.svg)](https://github.com/EmbarkStudios/spdx/actions?workflow=CI)
 [![Crates.io](https://img.shields.io/crates/v/spdx.svg)](https://crates.io/crates/spdx)
 [![Docs](https://docs.rs/spdx/badge.svg)](https://docs.rs/spdx)
 [![Contributor Covenant](https://img.shields.io/badge/contributor%20covenant-v1.4%20adopted-ff69b4.svg)](CODE_OF_CONDUCT.md)
 [![Embark](https://img.shields.io/badge/embark-open%20source-blueviolet.svg)](http://embark.rs)
 
-Helper crate for SPDX identifiers.
+Helper crate for [SPDX](https://spdx.org/about) [license expressions](https://spdx.org/spdx-specification-21-web-version#h.jxpfx0ykyb60).
 
 ## Usage