DOC: Added that threads can now contain a metadata stream #4900

Job	Run time
pytest on windows	6m 40s
Check code style issues	33s
Build & verify package	13s
pytest on 3.7 (crypto-lib: cryptography)	4m 45s
pytest on 3.8 (crypto-lib: cryptography)	4m 58s
pytest on 3.9 (crypto-lib: cryptography)	5m 9s
pytest on 3.10 (crypto-lib: cryptography)	4m 57s
pytest on 3.11 (crypto-lib: cryptography)	5m 4s
pytest on 3.12 (crypto-lib: cryptography)	6m 22s
pytest on 3.7 (crypto-lib: pycryptodome)	5m 6s
pytest on 3.7 (crypto-lib: none)	5m 5s
Combine & check coverage.	21s
	49m 13s

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