update pull readme (gum)

Author: gaudinnicolas

.d4g-tools/deploy/pull/readme.md

@@ -1,3 +1,10 @@
+# Install gum
+sudo mkdir -p /etc/apt/keyrings
+curl -fsSL https://repo.charm.sh/apt/gpg.key | sudo gpg --dearmor -o /etc/apt/keyrings/charm.gpg
+echo "deb [signed-by=/etc/apt/keyrings/charm.gpg] https://repo.charm.sh/apt/ * *" | sudo tee /etc/apt/sources.list.d/charm.list
+sudo apt update && sudo apt install gum
+
+
 # Content of cron file on sytem: