[vrt] add podlabels / change config / add default securitycontexts

[monotek]

Signed-off-by: André Bauer andre.bauer@staffbase.com

Which chart

• vrt

Which issue this PR fixes

• add podlabels
• change config
• add default securitycontexts
• update postgres dependency

What this PR does / why we need it

(optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged)

• fixes #

Special notes for your reviewer

Checklist

• [x] DCO signed
• [x] Chart Version bumped
• [x] README is up to date regarding breaking changes / upgrading instructions