Update white-space-collapse.json to preview in safari (mdn#21701)

* Update white-space-collapse.json

It was added in STP 182, and I also tested in STP and confirmed.
https://developer.apple.com/documentation/safari-technology-preview-release-notes/stp-release-182

Here is the link to the implementation:
WebKit/WebKit@30f3214

Also checked the layout tests in WPT, and they pass:
https://wpt.fyi/results/css/css-text/white-space/white-space-collapse-000.html?label=master&label=experimental&aligned
https://wpt.fyi/results/css/css-text/white-space/white-space-collapse-001.html?label=master&label=experimental&aligned

* Update white-space-collapse.json

delete unnecessary comma

css/properties/white-space-collapse.json

@@ -24,7 +24,7 @@
             "opera": "mirror",
             "opera_android": "mirror",
             "safari": {
-              "version_added": false
+              "version_added": "preview"
             },
             "safari_ios": "mirror",
             "samsunginternet_android": "mirror",