make the number of psks public

openmls/src/group/mls_group/config.rs

@@ -49,7 +49,7 @@ pub struct MlsGroupJoinConfig {
     /// can be decrypted. The default is 0.
     pub(crate) max_past_epochs: usize,
     /// Number of resumption secrets to keep
-    pub(crate) number_of_resumption_psks: usize,
+    pub number_of_resumption_psks: usize,
     /// Flag to indicate the Ratchet Tree Extension should be used
     pub(crate) use_ratchet_tree_extension: bool,
     /// Sender ratchet configuration