fix(FEC-10749): playlist by sources stuck

[yairans]

Description of the Changes

Issue: #370 moved the redirect default settings from setup to loadMedia
so sources could be undefined in kaltura-player constructor
Solution: pass empty object to sources to the local player if it's undefined

Solves FEC-10749

CheckLists

• changes have been done against master branch, and PR does not conflict
• new unit / functional tests have been added (whenever applicable)
• test are passing in local environment
• Travis tests are passing (or test results are not worse than on master branch :))
• Docs have been updated

[OrenMe]

@yairans can we add test for this? if no sources on constructor don't call configure