Add browser.closeContext() to v0.48 release notes

[ka3de]

What?

Adds an entry for the browser.closeContext() method under the UX improvements and enhancements section.

Why?

So it's properly documented as a new enhancement for the v0.48.0 release.

Checklist

• I have performed a self-review of my code.
• I have added tests for my changes.
• I have run linter locally (make lint) and all checks pass.
• I have run tests locally (make tests) and all tests pass.
• I have commented on my code, particularly in hard-to-understand areas.

Related PR(s)/Issue(s)

Code: grafana/xk6-browser#1074
Docs: grafana/k6-docs#1376

[ankur22]

LGTM

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

❗ No coverage uploaded for pull request base (release-notes-v0.48.0@723eba9). Click here to learn what that means.

❗ Current head 31d0745 differs from pull request most recent head 05284d5. Consider uploading reports for the commit 05284d5 to get more accurate results

Additional details and impacted files

@@                   Coverage Diff                    @@
##             release-notes-v0.48.0    #3419   +/-   ##
========================================================
  Coverage                         ?   73.11%           
========================================================
  Files                            ?      258           
  Lines                            ?    19650           
  Branches                         ?        0           
========================================================
  Hits                             ?    14367           
  Misses                           ?     4401           
  Partials                         ?      882           

Flag	Coverage Δ
ubuntu	73.04% <0.00%> (?)
windows	72.97% <0.00%> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.