PYTHON-5679 Optimize `ObjectId.str()` (#2657) #8705

Job	Run time
Docs Checks	38s
static	39s
Typing Tests (3.11)	39s
DocTest	28s
Typing Tests (3.10)	38s
Integration Tests	32s
Link Check	39s
Make an sdist	15s
CPython pypy-3.11-ubuntu-latest	26s
Test minimum dependencies and Python	27s
CPython 3.10-ubuntu-latest	27s
CPython 3.13t-ubuntu-latest	29s
Install from SDist and Test	20s
	6m 37s

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