reinstall ssh private keys from GH secrets (#8245)

package/deploy_package_index.sh

@@ -10,13 +10,23 @@ cd $(dirname "$0")
 
 set -e # Abort with error if anything here does not go as expected!
 
+# Install SSH private key from a GH Secret
+echo $GHCI_DEPLOY_KEY | base64 -d > esp8266_github_io_deploy
+eval "$(ssh-agent -s)"
+chmod 600 esp8266_github_io_deploy
+ssh-add esp8266_github_io_deploy
+mkdir -p ~/.ssh
+chmod go-w ~/.ssh
+echo -e "Host github.com\nStrictHostKeyChecking no\n" >> ~/.ssh/config
+chmod go-w  ~/.ssh/config
+
 # Clone the Github pages repository
 git clone [email protected]:esp8266/esp8266.github.io.git
 pushd esp8266.github.io
 
 # Copy from published release, ensure JSON valid
 rm -f stable/package_esp8266com_index.json
-wget "https://github.com/esp8266/Arduino/releases/download/"$tag"/package_esp8266com_index.json" -O stable/package_esp8266com_index.json
+wget https://github.com/esp8266/Arduino/releases/download/$tag/package_esp8266com_index.json -O stable/package_esp8266com_index.json
 cat stable/package_esp8266com_index.json | jq empty
 
 git add stable/package_esp8266com_index.json