adapter.getAttachment(): don't pass rev (#8792)

Previously the indexeddb adapter required rev to be passed through to
_getAttachment().  The implementation has now changed, and this value is no
longer required.

Author: alxndrsn

packages/node_modules/pouchdb-core/src/adapter.js

@@ -648,10 +648,6 @@ class AbstractPouchDB extends EventEmitter {
           }
           Object.keys(attachments).forEach((key) => {
             this._getAttachment(doc._id, key, attachments[key], {
-              // Previously the revision handling was done in adapter.js
-              // getAttachment, however since idb-next doesnt we need to
-              // pass the rev through
-              rev: doc._rev,
               binary: opts.binary,
               metadata: metadata,
               ctx: ctx