Generic weight averaging callback that supports EMA #14756

Job	Run time
pl-cpu (macOS-14, lightning, 3.10, 2.1)	20m 15s
pl-cpu (ubuntu-20.04, lightning, 3.10, 2.1)	15m 6s
pl-cpu (windows-2022, lightning, 3.10, 2.1)	17m 4s
pl-cpu (macOS-14, lightning, 3.11, 2.2.2)	20m 48s
pl-cpu (ubuntu-20.04, lightning, 3.11, 2.2.2)	15m 5s
pl-cpu (windows-2022, lightning, 3.11, 2.2.2)	15m 46s
pl-cpu (macOS-14, lightning, 3.11, 2.3)	21m 12s
pl-cpu (ubuntu-20.04, lightning, 3.11, 2.3)	15m 30s
pl-cpu (windows-2022, lightning, 3.11, 2.3)	1m 53s
pl-cpu (macOS-14, lightning, 3.12.7, 2.4.1)	22m 33s
pl-cpu (ubuntu-22.04, lightning, 3.12.7, 2.4.1)	20m 0s
pl-cpu (windows-2022, lightning, 3.12.7, 2.4.1)	20m 29s
pl-cpu (macOS-14, lightning, 3.12.7, 2.5.1)	22m 34s
pl-cpu (ubuntu-22.04, lightning, 3.12.7, 2.5.1)	21m 13s
pl-cpu (windows-2022, lightning, 3.12.7, 2.5.1)	20m 10s
pl-cpu (macOS-14, pytorch, 3.12.7, 2.5.1)	23m 14s
pl-cpu (ubuntu-22.04, pytorch, 3.12.7, 2.5.1)	21m 12s
pl-cpu (windows-2022, pytorch, 3.12.7, 2.5.1)	19m 46s
pl-cpu (macOS-14, lightning, 3.9, 2.1, oldest)	19m 11s
pl-cpu (ubuntu-20.04, lightning, 3.9, 2.1, oldest)	13m 32s
pl-cpu (windows-2022, lightning, 3.9, 2.1, oldest)	14m 48s
pl-cpu (macOS-14, pytorch, 3.9, 2.1)	21m 45s
pl-cpu (ubuntu-20.04, pytorch, 3.9, 2.1)	15m 34s
pl-cpu (windows-2022, pytorch, 3.9, 2.1)	17m 9s
	7h 15m 49s

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