Suppress webm file in media content e2e test

[VadimKovalenkoSNF]

Workaround for #1943

Problem:
vp9.webm file is no longer present in the I namespace, probably it shouldn't.

Workaround:
Temporarily disabled any vp9.webm checks till the root cause is found.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (99842b0) 73.27% compared to head (0e7d59a) 76.34%.
Report is 17 commits behind head on main.

❗ Current head 0e7d59a differs from pull request most recent head 5c45741. Consider uploading reports for the commit 5c45741 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1944      +/-   ##
==========================================
+ Coverage   73.27%   76.34%   +3.07%     
==========================================
  Files          39       37       -2     
  Lines        3106     2985     -121     
  Branches      687      653      -34     
==========================================
+ Hits         2276     2279       +3     
+ Misses        711      611     -100     
+ Partials      119       95      -24     

Files	Coverage Δ
src/mwoffliner.lib.ts	74.81% <100.00%> (+0.09%)	⬆️
src/util/const.ts	100.00% <100.00%> (ø)

... and 10 files with indirect coverage changes

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[kelson42]

What is the explanation about:

• The problem?
• The solution/workaround?

[VadimKovalenkoSNF]

@kelson42 I updated PR description.

[kelson42]

Approved, but there is a real bug somehwere either in Mediawiki or in MWoffliner

[kelson42]

@VadimKovalenkoSNF please fix conflict and merge