ci: enable docsrs only on rustdoc

Author: tottoto

.github/workflows/ci.yml

@@ -89,10 +89,8 @@ jobs:
       # check for missing docs
       - name: cargo check
         run: cargo check --all-features
-        env:
-          RUSTFLAGS: "--cfg docsrs"
 
       - name: cargo doc
         run: cargo rustdoc --all-features -- -D 'rustdoc::broken_intra_doc_links'
         env:
-          RUSTFLAGS: "--cfg docsrs"
+          RUSTDOCFLAGS: "--cfg docsrs"