fix: add accept headers for MLT and MVT

[CommanderStorm]

As requested in maplibre/maplibre-style-spec#1251 (comment) we should include the Accept header.

This is important for us as a tile server, given that we otherwise have no clue if we should transcode an MLT <-> MVT source.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.81%. Comparing base (7499aa3) to head (dcb83a7).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7483      +/-   ##
==========================================
+ Coverage   92.80%   92.81%   +0.01%     
==========================================
  Files         290      290              
  Lines       24087    24095       +8     
  Branches     5099     5103       +4     
==========================================
+ Hits        22354    22364      +10     
+ Misses       1733     1731       -2     

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[nyurik]

lgtm

[CommanderStorm]

just to be save, lets put this under v6.
I don't think this is breaking, but we never know what people are doing with headers... maybe WAF filtering for incoming requests or something bad.. Not sure

[HarelM]

Looks good, thanks, let's wait for version 6 with this.

[HarelM]

See discussion here:

• Supporting content negotiation via Accept maplibre-native#4236

And PR here:

• fix: add the accept header to http requests maplibre-native#4231

Let's finish the discussion there first before merging this.

Needs discussion.