pass the runner clock into batch triggers

[aIbrahiim]

• FnApi batch triggers had no clock, so a processing-time trigger crashed or fired immediately
• Pass the runner clock through and leave future processing-time timers queued
• Split out of fix leader board trigger #40370 so the leader board example can be reviewed on its own

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[codecov]

Codecov Report

❌ Patch coverage is 72.72727% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 56.20%. Comparing base (78c9e10) to head (5e79a0b).
⚠️ Report is 59 commits behind head on master.

Files with missing lines	Patch %	Lines
sdks/python/apache_beam/transforms/trigger.py	66.66%	3 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master   #40429      +/-   ##
============================================
+ Coverage     56.15%   56.20%   +0.05%     
  Complexity     2288     2288              
============================================
  Files          1121     1123       +2     
  Lines        177193   178214    +1021     
  Branches       1489     1489              
============================================
+ Hits          99504   100168     +664     
- Misses        75168    75525     +357     
  Partials       2521     2521              

Flag	Coverage Δ
python	79.67% <72.72%> (-0.19%)	⬇️

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