Bump to version 4.3.0rc1 #3003

Job	Run time
Unit Tests + Kernel (Python 3.14)	18m 44s
check-linting (3.9)	1m 57s
check-linting (3.14)	16m 28s
check-linting (3.13)	1m 48s
check-types (3.9)	3m 14s
check-types (3.14)	16m 56s
Unit Tests + PyArrow (Python 3.9, min deps)	4m 33s
Unit Tests + PyArrow (Python 3.10, min deps)	4m 36s
Unit Tests + Kernel (Python 3.13)	4m 15s
Unit Tests + Kernel (Python 3.11)	4m 18s
Unit Tests (Python 3.14, min deps)	18m 24s
Unit Tests + PyArrow (Python 3.13, default deps)	4m 16s
Unit Tests (Python 3.9, min deps)	3m 52s
Unit Tests (Python 3.12, default deps)	3m 29s
Unit Tests + PyArrow (Python 3.9, default deps)	4m 17s
Unit Tests (Python 3.14, default deps)	18m 22s
Unit Tests (Python 3.11, min deps)	3m 55s
Unit Tests + PyArrow (Python 3.10, default deps)	4m 11s
check-linting (3.10)	1m 49s
check-linting (3.12)	1m 48s
Unit Tests + Kernel (Python 3.12)	4m 20s
check-types (3.13)	1m 58s
Unit Tests (Python 3.10, default deps)	3m 31s
Unit Tests + PyArrow (Python 3.11, min deps)	4m 38s
Unit Tests + PyArrow (Python 3.11, default deps)	4m 7s
Unit Tests (Python 3.10, min deps)	3m 54s
Unit Tests (Python 3.13, default deps)	3m 27s
Unit Tests + PyArrow (Python 3.14, default deps)	19m 12s
Unit Tests + PyArrow (Python 3.14, min deps)	19m 10s
check-linting (3.11)	1m 49s
check-types (3.10)	2m 5s
Unit Tests (Python 3.11, default deps)	3m 30s
Unit Tests + PyArrow (Python 3.12, default deps)	4m 5s
check-types (3.12)	2m 3s
Unit Tests (Python 3.9, default deps)	3m 36s
Unit Tests + Kernel (Python 3.10)	4m 25s
check-types (3.11)	1m 56s
	3h 48m 58s

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