bug: use explicit path

* Update .github/workflows/publish_docs.yml

Co-authored-by: Philip Jenvey <[email protected]>

.github/workflows/publish_docs.yml

@@ -38,14 +38,15 @@ jobs:
         env:
             MDBOOK_ENV: 0.4.24
             MERMAID_ENV: 0.12.6
-            DEST_DIR: ~/.cargo/bin
+            DEST_DIR: /home/runner/.cargo/bin
         steps:
             # these are other job descriptions to call.
             - uses: actions/checkout@v3
             - name: Configure rust  # TODO: can we export building rust and installing mdbook as an artifact and reuse it?
               run: |
                 curl --proto '=https' --tlsv1.2 https://sh.rustup.rs -sSf -y | sh
                 rustup update
+                export PATH=$PATH:$DEST_DIR
             - name: Install mdBook
               run: |
                 curl -sSL "https://github.com/rust-lang/mdBook/releases/download/v$MDBOOK_ENV/mdbook-v$MDBOOK_ENV-x86_64-unknown-linux-gnu.tar.gz" | tar -xz --directory $DEST_DIR