Add libdbi-drivers as optional dependency (FS#58277)

PKGBUILD

@@ -4,7 +4,7 @@
 
 pkgname=gnucash
 pkgver=3.0
-pkgrel=5
+pkgrel=6
 pkgdesc='Personal and small-business financial-accounting application'
 arch=(x86_64)
 url='https://gnucash.org/'
@@ -12,6 +12,7 @@ license=(GPL)
 depends=(aqbanking boost-libs guile libdbi webkit2gtk)
 makedepends=(boost cmake gmock libdbi-drivers libmariadbclient postgresql-libs)
 optdepends=('gnucash-docs: documentation'
+            'libdbi-drivers: open and save data into SQL database'
             'perl-date-manip: stock information lookups'
             'perl-finance-quote: stock information lookups')
 options=(!emptydirs)