gradle: adopt _bash_it_find_in_ancestor()

plugins/available/gradle.plugin.bash

@@ -3,19 +3,10 @@ about-plugin 'Add a gw command to use gradle wrapper if present, else use system
 
 function gw() {
   local file="gradlew"
-  local curr_path="${PWD}"
-  local result="gradle"
+  local result
 
-  # Search recursively upwards for file.
-  until [[ "${curr_path}" == "/" ]]; do
-    if [[ -e "${curr_path}/${file}" ]]; then
-      result="${curr_path}/${file}"
-      break
-    else
-      curr_path=$(dirname "${curr_path}")
-    fi
-  done
+  result="$(_bash-it-find-in-ancestor "${file}")"
 
   # Call gradle
-  "${result}" $*
+  "${result:-gradle}" $*
 }