Move from gitbook to docusaurus - backport (#10970) (#11029)

* Move v1.2 to docusaurus

* Fixup travis conifg

Co-authored-by: publish-docs.sh <maintainers@solana.com>

docs/build-cli-usage.sh

@@ -3,6 +3,9 @@ set -e
 
 cd "$(dirname "$0")"
 
+# shellcheck source=ci/rust-version.sh
+source ../ci/rust-version.sh stable
+
 : "${rust_stable:=}" # Pacify shellcheck
 
 usage=$(cargo +"$rust_stable" -q run -p solana-cli -- -C ~/.foo --help | sed -e 's|'"$HOME"'|~|g' -e 's/[[:space:]]\+$//')