Upgrade translations, add Spanish (Cuba) and Bengali.

...riarproject/briar/desktop/settings/UnencryptedSettings.kt

...top/src/main/resources/strings/BriarDesktop_ar.properties

...top/src/main/resources/strings/BriarDesktop_bg.properties

...top/src/main/resources/strings/BriarDesktop_bn.properties

...top/src/main/resources/strings/BriarDesktop_ca.properties

...top/src/main/resources/strings/BriarDesktop_cs.properties

...top/src/main/resources/strings/BriarDesktop_de.properties

...top/src/main/resources/strings/BriarDesktop_es.properties

.../src/main/resources/strings/BriarDesktop_es_CU.properties

...top/src/main/resources/strings/BriarDesktop_fa.properties

...top/src/main/resources/strings/BriarDesktop_fr.properties

...top/src/main/resources/strings/BriarDesktop_gl.properties

...top/src/main/resources/strings/BriarDesktop_he.properties

...top/src/main/resources/strings/BriarDesktop_hu.properties

...top/src/main/resources/strings/BriarDesktop_is.properties

...top/src/main/resources/strings/BriarDesktop_it.properties

...top/src/main/resources/strings/BriarDesktop_ja.properties

...top/src/main/resources/strings/BriarDesktop_ka.properties

...top/src/main/resources/strings/BriarDesktop_ko.properties

...top/src/main/resources/strings/BriarDesktop_lt.properties