Add pull request:write permissions to nightly build Workflow

[guineveresaenger]

Proposed fix for #2145.

update: it looks like the nightly build needs more than pull request permissions: https://github.com/pulumi/pulumi-aws-native/actions/runs/14070213304/job/39402424273#step:16:6

update: the nightly job pushes directly to a branch on origin so it needs contents permissions as well.
Successful run here: https://github.com/pulumi/pulumi-aws-native/actions/runs/14070892002/job/39404595733
Generated PR here: #2149

[github-actions]

Does the PR have any schema changes?

Looking good! No breaking changes found.
No new resources/functions.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 50.80%. Comparing base (914e3e9) to head (d0575d8).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #2148   +/-   ##
=======================================
  Coverage   50.80%   50.80%           
=======================================
  Files          49       49           
  Lines        7088     7088           
=======================================
  Hits         3601     3601           
  Misses       3235     3235           
  Partials      252      252           

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[mjeffryes]

We'll need to get this into ci-mgmt as well

[t0yv0]

Could we do so right away?

# WARNING: This file is autogenerated - changes will be overwritten if not made via https://github.com/pulumi/ci-mgmt

this is liable to be wiped out.

[guineveresaenger]

yep, closing in favor of pulumi/ci-mgmt#1468