Enable SQLITE_ENABLE_COLUMN_METADATA by default (amalgamation builds)

Discussion on [the forum](https://groups.google.com/g/python-sqlite/c/w_icS7yhEsE)

A quick survey of Linux distros (using images via distrobox) shows the following with the option on:

* Rocky (hence Fedora, RHEL)
* Ubuntu, Debian
* OpenSuse
* Arch

