[backport 2.3.x] API(str dtype): Raise on StringDtype for unary op + … #21550

Job	Run time
Linux-32-bit	20m 8s
Linux-Musl	22m 13s
python-dev (macOS-13)	28m 18s
python-dev (macOS-14)	16m 10s
python-dev (windows-latest)	27m 1s
python-dev (ubuntu-22.04)	25m 2s
macos-13 actions-310.yaml	39m 21s
macos-13 actions-312.yaml	43m 9s
macos-13 actions-39.yaml	32m 55s
macos-13 actions-311.yaml	37m 3s
macos-14 actions-310.yaml	25m 28s
macos-14 actions-311.yaml	24m 14s
macos-14 actions-312.yaml	27m 57s
macos-14 actions-39.yaml	32m 50s
windows-latest actions-311.yaml	40m 52s
windows-latest actions-312.yaml	44m 58s
windows-latest actions-310.yaml	38m 37s
windows-latest actions-39.yaml	37m 15s
ubuntu-latest actions-310.yaml	53m 49s
Copy-on-Write 3.10 (warnings)	29m 30s
Copy-on-Write 3.10	28m 18s
ubuntu-latest actions-311.yaml	50m 34s
Future infer strings (without pyarrow)	50m 48s
Locale: zh_CN	27m 11s
Copy-on-Write 3.11	27m 40s
Copy-on-Write 3.11 (warnings)	27m 23s
Locale: it_IT	26m 28s
Downstream Compat	6m 14s
Numpy Dev	22m 25s
Pyarrow Nightly	25m 16s
ubuntu-latest actions-312.yaml	38m 28s
Future infer strings	38m 57s
Copy-on-Write 3.12	31m 16s
ubuntu-latest actions-39.yaml	49m 33s
Copy-on-Write 3.9 (warnings)	28m 46s
Copy-on-Write 3.9	29m 19s
Minimum Versions	27m 10s
Pypy	7m 50s
	19h 50m 26s

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