Update parserTests.txt to latest from mediawiki/core.

The latest upstream parser tests have 5 new tests (3 Parsoid serializer,
2 parser) & fixed 4 tests ( https://gerrit.wikimedia.org/r/#/c/57079/ )
which:

* Updated html output of two parsoid-centric tests to reflect
  changes in parsoid output.
* Updated 'disabled parsoid' options on two tests to 'parsoid'.
* Added three more tests for the Parsoid serializer.
* Added two tests documenting differences in PHP and Parsoid
  output for overlapping HTML tags (sometimes seen on wikipedia
  pages).

Change-Id: I8202973b36ceefaaca2a2e923a777a1286231a68
Merge "Update parserTests.txt to latest from mediawiki/core."