STY: Modify error messages in PdfWriter #5494

Job	Run time
Build & verify package	11s
Build & verify package	11s
Check code style issues	41s
Check code style issues	41s
pytest on windows	6m 48s
pytest on windows	6m 55s
pytest on 3.8 (crypto-lib: cryptography)	5m 30s
pytest on 3.8 (crypto-lib: cryptography)	5m 30s
pytest on 3.9 (crypto-lib: cryptography)	5m 35s
pytest on 3.9 (crypto-lib: cryptography)	5m 35s
pytest on 3.10 (crypto-lib: cryptography)	5m 38s
pytest on 3.10 (crypto-lib: cryptography)	5m 38s
pytest on 3.11 (crypto-lib: cryptography)	5m 23s
pytest on 3.11 (crypto-lib: cryptography)	5m 23s
pytest on 3.12 (crypto-lib: cryptography)	7m 36s
pytest on 3.12 (crypto-lib: cryptography)	7m 36s
pytest on 3.13 (crypto-lib: cryptography)	7m 37s
pytest on 3.13 (crypto-lib: cryptography)	7m 37s
pytest on 3.8 (crypto-lib: pycryptodome)	5m 18s
pytest on 3.8 (crypto-lib: pycryptodome)	5m 18s
pytest on 3.8 (crypto-lib: none)	5m 18s
pytest on 3.8 (crypto-lib: none)	5m 18s
Combine & check coverage.	17s
Combine & check coverage.	17s
	1h 51m 51s

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