vendor: update go.etcd.io/bbolt v1.3.4

full diff: https://github.com/etcd-io/bbolt/compare/v1.3.3...v1.3.4

- Fix unsafe pointer conversions caught by Go 1.14 checkptr
- Fix unexpected delete bucket error: "delete bucket: incompatible value"
- Add support for aix
- Add go.mod
- db.Path() resolves to db.file.Name()

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

vendor/go.etcd.io/bbolt/cursor.go

@@ -366,7 +366,7 @@ func (c *Cursor) node() *node {
 	}
 	for _, ref := range c.stack[:len(c.stack)-1] {
 		_assert(!n.isLeaf, "expected branch node")
-		n = n.childAt(int(ref.index))
+		n = n.childAt(ref.index)
 	}
 	_assert(n.isLeaf, "expected leaf node")
 	return n