Enable to skip update checks from pom properties

[rmannibucau]

Follow up of #3350 (comment) since it is really bothering to not be able to disable update check for project in time - when you don't work on a single "everyday" project and disabling it globally is rarely the desired behavior (it is really a per project thing) but the properties were not read as expected so this PR ensures it is the case.

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Fixes #<issue_number_goes_here> 🛠️

[slawekjaranowski]

even more there is the problem to settings environment variable with dots like jib.disableUpdateChecks on unix systems

I have tested with zsh and bash on macOs ...

zsh

export jib.disableUpdateChecks=true 
export: not valid in this context: jib.disableUpdateChecks

bash

export jib.disableUpdateChecks=true
bash: export: `jib.disableUpdateChecks=true': not a valid identifier

so I can not disable it at easy way