Fix input error on generating password and salt in install script (#3051)

* Fix potential input error on password generation

This happens on macOS systems when a different locale is
explicitly set.

* Don't use a masked variable name

deploy/install.sh

@@ -248,8 +248,13 @@ urlencode() {
 }
 
 generate_password() {
-    # Picked up the following method of generation from : https://gist.github.com/earthgecko/3089509
-    LC_CTYPE=C tr -dc 'a-zA-Z0-9' < /dev/urandom | fold -w 13 | head -n 1
+    local gen_string="$(/usr/bin/python -c 'import random, string; print("".join(random.choice(string.ascii_letters + string.digits) for _ in range(13)))' 2>/dev/null)"
+    if [[ -n $gen_string ]]; then
+        echo "$gen_string"
+    else
+        # Picked up the following method of generation from : https://gist.github.com/earthgecko/3089509
+        LC_ALL=C tr -dc 'a-zA-Z0-9' < /dev/urandom | fold -w 13 | head -n 1
+    fi
 }
 
 confirm() {