fixes to readme checks

- fix the workflow name
- fix the job name
- rm the `needs` dependency
- put in the correct version to the readme (I had previously put an
intentionally incorrect one, to prove this script works; and then I
forgot to remove it)

In service of (and may resolve) #221

.github/workflows/readme-checks.yml

@@ -1,4 +1,4 @@
-name: rust
+name: Documentation
 
 on:
   push:
@@ -9,9 +9,8 @@ env:
   CARGO_TERM_COLOR: always
 
 jobs:
-  check msrv:
+  check-msrv:
     runs-on: ubuntu-latest
-    needs: build
     steps:
     - uses: actions/checkout@v4
     - name: find version mentioned in readme

README.md

@@ -188,7 +188,7 @@ cat oncall.md | mdq ':-: * :-: 2024-01-15'
 
 # Development
 
-Requires rustc >= 1.20.0
+Requires rustc >= 1.78.0
 
 ```bash
 cargo build