fix: make prepare wait for add to finish

[jcesarmobile]

prepare is being run before add command finish because fs.lstat is async and the createProject is resolving before fs.lstat finishes.

This PR changes fs.lstat to fs.lstatSync to make the directory check sync and avoid to resolve before all create work is done.

Closes #725

[l3ender]

Nice find! I played around with the prepare/create scripts but couldn't find what was aysnc and breaking the prepare script (not familiar enough with fs, I guess).

[ath0mas]

I confirm no more error using your fork & branch, for my previous repro #725 (comment)
💯

[erisu]

Changes LGTM 👍

Also tested following cases

Environment

$ cordova -v
9.0.0 (cordova-lib@9.0.1)

Test Cases

Updated config.xml before platform add

$ cordova create iosTest2 com.foobar.iosTest2 iosTest2 && $_

Creating a new cordova project.

$ vi config.xml

--> ADDED <preference name="WKWebViewOnly" value="true" />

$ cordova platform add ../cordova-ios-5.2.0-dev.tgz

Using cordova-fetch for ../cordova-ios-5.2.0-dev.tgz
Warning: using prerelease platform ios@5.2.0-dev.
Use 'cordova platform add ios@latest' to add the latest published version instead.
Adding ios project...
Creating Cordova project for the iOS platform:
	Path: platforms/ios
	Package: com.foobar.iosTest2
	Name: iosTest2
iOS project created with cordova-ios@5.2.0-dev
Plugin 'cordova-plugin-whitelist' found in config.xml... Migrating it to package.json
Discovered saved plugin "cordova-plugin-whitelist". Adding it to the project
Installing "cordova-plugin-whitelist" for ios
Adding cordova-plugin-whitelist to package.json

$ cordova build ios --release --device

...
** ARCHIVE SUCCEEDED **
...
** EXPORT SUCCEEDED **
...

Updated config.xml after platform add before build

$ cordova create iosTest2 com.foobar.iosTest2 iosTest2 && $_

Creating a new cordova project.

$ cordova platform add ../cordova-ios-5.2.0-dev.tgz

Using cordova-fetch for ../cordova-ios-5.2.0-dev.tgz
Warning: using prerelease platform ios@5.2.0-dev.
Use 'cordova platform add ios@latest' to add the latest published version instead.
Adding ios project...
Creating Cordova project for the iOS platform:
	Path: platforms/ios
	Package: com.foobar.iosTest2
	Name: iosTest2
iOS project created with cordova-ios@5.2.0-dev
Plugin 'cordova-plugin-whitelist' found in config.xml... Migrating it to package.json
Discovered saved plugin "cordova-plugin-whitelist". Adding it to the project
Installing "cordova-plugin-whitelist" for ios
Adding cordova-plugin-whitelist to package.json

$ vi config.xml

--> ADDED <preference name="WKWebViewOnly" value="true" />

$ cordova build ios --release --device

...
** ARCHIVE SUCCEEDED **
...
** EXPORT SUCCEEDED **
...