Add libsqlcipher0 to Depends for DEB packages

[pludi]

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Based on the information from #1233 I checked for the inclusion of libsqlcipher0 in Debian-based distributions. Debian itself includes it since Buster (mid 2019), and all currently supported Debian and Ubuntu versions ship it. Checking the package databases of major Debian/Ubuntu derivates (Linux Mint, MX Linux, Pop_OS!, Devuan, antiX) shows them either shipping it too or pulling it from the Ubuntu repos.

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[t3chguy]

Debian itself includes it since Buster (mid 2019)

Debian Stretch & Jessie are still supported in ELTS
https://www.freexian.com/lts/extended/docs/debian-9-support/
https://www.freexian.com/lts/extended/docs/debian-8-support/

Checking the package databases of major Debian/Ubuntu derivates (Linux Mint, MX Linux, Pop_OS!, Devuan, antiX) shows them either shipping it too or pulling it from the Ubuntu repos.

Sure but we try to support more than just that list of major derivatives you came up with, one random example, looks like deepin lacks a libsqlcipher0

https://community-packages.deepin.com/deepin/pool/main/libs/

[pludi]

Deepin has the libsqlcipher0 package, just at a different location: https://community-packages.deepin.com/deepin/apricot/pool/main/s/sqlcipher/

Regarding Debian 8 and 9, that service apparently isn't for the whole distribution, but instead customers have to provide a list of required packages. As such I'd wager that anyone running Element Desktop on such an old machine and with the requirement for cipher message search probably already has it requested from them and/or installed through other means.

[t3chguy]

It is worth noting that the dependency is on its way out with us wanting to move to static sqlcipher linking #1001