fix(build): Prereq check - support paths with spaces.

Prereq check before `yarn build` fails when there are spaces in the
path. This is common for WSL2 on windows. For example, mvn is in the
path at `/mnt/c/Program Files/`.

Testing - Ran check on linux paths and windows paths with and without
spaces. Tested with correct version, wrong version, and missing dep.

fixes #9749

scripts/check-prerequisites.sh

@@ -22,7 +22,7 @@ check_which() {
 
     w=$(which ${app}) || w=""
 
-    if [ -z $w ] || [ $w == "$app not found" ]
+    if [ -z "$w" ] || [ "$w" == "$app not found" ]
     then
         die "Missing dependency: $app. Install $app >= $min"
     else