Add Content-Length header for job queue requests

Include the Content-Length header in job queue POST requests to meet the
requirement by certain servers, avoiding HTTP 411 responses.

Bug: 72274
Change-Id: Icf34bca58c792225d735d576213d6887015459ca
Bump version number

Change-Id: I3c4dcdd603f127f9b2f73a5e5975caecc43278bd
Merge branch 'REL1_23' of https://github.com/wikimedia/mediawiki-core into REL1_23