Update career progression images and text

[carkod]

Done

• Update images
• Update text according to copy doc

QA

• Go to https://canonical-com-906.demos.haus/careers/company-culture/progression scroll down to "Explore diverse roles" section and check that it's been updated with the new images
• Check also against copy doc text update

Issue / Card

Fixes https://warthogs.atlassian.net/browse/WD-4595?atlOrigin=eyJpIjoiYzQ2NWQ5ZGZkM2JiNDRhNmE0M2M3Mzk2MTg2MWZlMzMiLCJwIjoiaiJ9
Closes https://warthogs.atlassian.net/browse/WD-4141?atlOrigin=eyJpIjoiMmE0ZmVhODNkOGNlNGMyZDgyNDhiNzIzOWZkMjY3N2IiLCJwIjoiaiJ9

Screenshots

[if relevant, include a screenshot]

[webteam-app]

Demo starting at https://canonical-com-906.demos.haus

[codecov]

Codecov Report

Merging #906 (28d4e79) into main (7aea519) will not change coverage.
The diff coverage is n/a.

❗ Current head 28d4e79 differs from pull request most recent head 405cf9d. Consider uploading reports for the commit 405cf9d to get more accurate results

@@           Coverage Diff           @@
##             main     #906   +/-   ##
=======================================
  Coverage   60.34%   60.34%           
=======================================
  Files          10       10           
  Lines         764      764           
=======================================
  Hits          461      461           
  Misses        303      303           

Flag	Coverage Δ
python	60.34% <ø> (ø)

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Impacted Files	Coverage Δ
webapp/static_data.py	100.00% <ø> (ø)