make coalesce compile friendly

[ValterH]

Update coalesce to be torch compiled without graph breaks.

[akihironitta]

Any chance you could add a quick test case that reproduces the issue?

[ValterH]

@akihironitta I added a test case, but had to remove the error message as torch._check requires the message to be callable and passing a lambda function causes a graph break during compilation.

[codecov]

Codecov Report

❌ Patch coverage is 66.66667% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 85.08%. Comparing base (c211214) to head (1bfbbf2).
⚠️ Report is 137 commits behind head on master.

Files with missing lines	Patch %	Lines
torch_geometric/utils/_coalesce.py	66.66%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #10522      +/-   ##
==========================================
- Coverage   86.11%   85.08%   -1.03%     
==========================================
  Files         496      510      +14     
  Lines       33655    35967    +2312     
==========================================
+ Hits        28981    30603    +1622     
- Misses       4674     5364     +690     

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

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.