Minor mbtiles doc cleanups #1988

Job	Run time
Build aarch64-apple-darwin	14m 23s
Build aarch64-unknown-linux-gnu	11m 52s
Build debian-x86_64	9m 57s
Build x86_64-apple-darwin	11m 10s
Build x86_64-pc-windows-msvc	23m 32s
Build x86_64-unknown-linux-gnu	14m 34s
Build docker images	1m 12s
Test Legacy DB (postgis/postgis:11-3.0-alpine, postgres, disable)	10m 50s
Test x86_64-apple-darwin	7m 42s
Test Legacy DB (postgis/postgis:14-3.3-alpine, postgres, disable)	9m 23s
Test x86_64-pc-windows-msvc	1m 11s
Test Legacy DB (postgis/postgis:15-3.3, postgres -c ssl=on -c ssl_cert_file=/etc/ssl/certs/ssl-ce...	10m 21s
Test x86_64-unknown-linux-gnu	7m 45s
Package aarch64-apple-darwin	8s
Package aarch64-unknown-linux-gnu	7s
Package x86_64-apple-darwin	18s
Package x86_64-pc-windows-msvc	18s
Package x86_64-unknown-linux-gnu	11s
Package debian-x86_64	8s
CI Finished	3s
	2h 15m 5s

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