CXX-2811 mark server version 3.6 as eol from driver's pov (min server version as 4.0, minwireversion as 7.0) (#1177)

Author: Julia-Garland

src/mongocxx/test/client_helpers.cpp

@@ -297,10 +297,6 @@ stdx::optional<bsoncxx::document::value> parse_test_file(std::string path) {
     return bsoncxx::from_json(stream.str());
 }
 
-bool supports_collation(const client& client) {
-    return get_max_wire_version(client) >= 5;
-}
-
 bsoncxx::document::value transform_document(bsoncxx::document::view view, const xformer_t& fcn) {
     bsoncxx::builder::basic::array context;
 

src/mongocxx/test/client_helpers.hh

@@ -125,15 +125,6 @@ std::string get_hosts(const client& client = {uri{}, add_test_server_api()});
 ///
 stdx::optional<bsoncxx::document::value> parse_test_file(std::string path);
 
-//
-// Determines whether or not the given client supports the collation feature, by running the
-// "hello" command.
-//
-// Throws mongocxx::operation_exception if the operation fails, or the server reply is
-// malformed.
-//
-bool supports_collation(const client& client);
-
 using item_t = std::pair<stdx::optional<stdx::string_view>, bsoncxx::types::bson_value::view>;
 using xformer_t = std::function<stdx::optional<item_t>(item_t, bsoncxx::builder::basic::array*)>;