[Website] Update case-studies logo images

[bullet03]

Resolves #22799

• change css prop from width to max-width to fit logos with rectangle images, so it wouldn't stretch too much (Intuit, Paloalto, Ricardo, Seznam case-studies)
• add case-study-opinion-img-center class to center logos with narrow images (Hop, Lyft case-studies)

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[alevtinaboiko]

Verified, works as expected. Reviewed and tested by QA

[bullet03]

@pcoet, could you, please, help with review of current PR?

[bullet03]

@pabloem, could you, please, help with merging?

[bullet03]

@aromanenko-dev, could you kindly help with merge? PR was approved.

[pabloem]

my apologies