Remove redis from directory docker-compose

[spacebear21]

Redis is no longer needed to run the directory service.

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[spacebear21]

Converting to Draft because I'm not sure whether PJ_STORAGE_DIR needs to be set explicitly? cc @nothingmuch

[coveralls]

Pull Request Test Coverage Report for Build 17867660605

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.01%) to 84.743%

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Totals
Change from base Build 17867308905:	0.01%
Covered Lines:	8559
Relevant Lines:	10100

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💛 - Coveralls

[nothingmuch]

it does, i didn't set a default value because the one for ohttp-keys seemed a bit cavalier just going with something in the current directory

we could figure out if we want to use xdg directories (not sure that's advised for a service) or maybe /var/lib/payjoin-directory or /var/run/payjoin-directory, but i think my preferred approach is to require it to be set seems safest

[spacebear21]

This change also requires an up-to-date docker image for payjoin-directory so marking this as blocked until then.