Add new TiDBVectorStore vectorstore

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🦙 MegaLinter status: ✅ SUCCESS

Descriptor	Linter	Files	Fixed	Errors	Elapsed time
✅ PYTHON	bandit	2		0	5.39s
✅ PYTHON	black	2	0	0	1.72s
✅ PYTHON	flake8	2		0	0.94s
✅ PYTHON	isort	2	0	0	0.21s
✅ PYTHON	pylint	2		0	8.01s

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