feat(browser-support): Add safari to list of optimal browsers

interface_config.js

     // has a suboptimal experience. Browsers which are not listed as optimal or
     // unsupported are considered suboptimal. Valid values are:
     // chrome, chromium, edge, electron, firefox, nwjs, opera, safari
-    OPTIMAL_BROWSERS: [ 'chrome', 'chromium', 'firefox', 'nwjs', 'electron' ],
+    OPTIMAL_BROWSERS: [ 'chrome', 'chromium', 'firefox', 'nwjs', 'electron', 'safari' ],
 
     // Browsers, in addition to those which do not fully support WebRTC, that
     // are not supported and should show the unsupported browser page.

react/features/base/environment/environment.js

     'chrome',
     'electron',
     'firefox',
-    'nwjs'
+    'nwjs',
+    'safari'
 ];
 
 const DEFAULT_UNSUPPORTED_BROWSERS = [];