[REM] core: deprecated Environment methods

Part-of: odoo/odoo#98138

odoo/api.py

@@ -475,22 +475,6 @@ class Environment(Mapping):
     names to models. It also holds a cache for records, and a data
     structure to manage recomputations.
     """
-    @classproperty
-    def envs(cls):
-        raise NotImplementedError(
-            "Since Odoo 15.0, Environment.envs no longer works; "
-            "use cr.transaction or env.transaction instead."
-        )
-
-    @classmethod
-    @contextmanager
-    def manage(cls):
-        warnings.warn(
-            "Since Odoo 15.0, Environment.manage() is useless.",
-            DeprecationWarning, stacklevel=2,
-        )
-        yield
-
     def reset(self):
         """ Reset the transaction, see :meth:`Transaction.reset`. """
         self.transaction.reset()
@@ -701,16 +685,6 @@ class Environment(Mapping):
         lazy_property.reset_all(self)
         self.transaction.clear()
 
-    def clear_upon_failure(self):
-        """ Context manager that rolls back the environments (caches and pending
-            computations and updates) upon exception.
-        """
-        warnings.warn(
-            "Since Odoo 15.0, use cr.savepoint() instead of env.clear_upon_failure().",
-            DeprecationWarning, stacklevel=2,
-        )
-        return self.cr.savepoint()
-
     def invalidate_all(self, flush=True):
         """ Invalidate the cache of all records.