fix(news_app): Apply size constraint in NewsFeedIcon

[provokateurin]

#2448 accidentally removed the size constraint which lead to some jumping around while loading the icons.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 29.92%. Comparing base (ac73ec9) to head (0a04fcf).
Report is 12 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2472   +/-   ##
=======================================
  Coverage   29.92%   29.92%           
=======================================
  Files         332      332           
  Lines      124414   124414           
=======================================
  Hits        37231    37231           
  Misses      87183    87183           

Flag	Coverage Δ		*Carryforward flag
account_repository	99.64% <ø> (ø)
cookie_store	99.48% <ø> (ø)		Carriedforward from ac73ec9
dashboard_app	96.05% <ø> (ø)
dynamite	31.08% <ø> (ø)		Carriedforward from ac73ec9
dynamite_end_to_end_test	61.69% <ø> (ø)		Carriedforward from ac73ec9
dynamite_runtime	85.40% <ø> (ø)		Carriedforward from ac73ec9
neon_dashboard	96.05% <ø> (ø)		Carriedforward from ac73ec9
neon_framework	43.65% <ø> (ø)
neon_http_client	93.28% <ø> (ø)		Carriedforward from ac73ec9
neon_notifications	100.00% <ø> (ø)		Carriedforward from ac73ec9
neon_talk	99.45% <ø> (ø)		Carriedforward from ac73ec9
nextcloud	25.90% <ø> (ø)		Carriedforward from ac73ec9
notifications_app	100.00% <ø> (ø)
sort_box	90.90% <ø> (ø)		Carriedforward from ac73ec9
talk_app	99.09% <ø> (ø)

*This pull request uses carry forward flags. Click here to find out more.