FormatJson::parse( TRY_FIXING ) - remove trailing commas

Removes trailing commas from json text when parsing
Solves very common cases like [1,2,3,]

Resulting status will be set to OK but not Good to warn caller

Change-Id: Ic0eb0a711da3ae578d6bb58d7474279d6845a4a7
(cherry picked from commit 289d3e4f0000503fac5326e986f27e0b1d924c7f)