sorcery: Add API to insert/remove a wizard to/from an object type's list

Currently you can 'apply' a wizard to an object type but the wizard
always goes at the end of the object type's wizard list.  This patch
adds a new ast_sorcery_insert_wizard_mapping function that allows
you to insert a wizard anyplace in the list.  I.E.  You could
add a caching wizard to an object type and place it before all
wizards.

ast_sorcery_get_wizard_mapping_count and
ast_sorcery_get_wizard_mapping were added to allow examination
of the mapping list.

ast_sorcery_remove_mapping was added to remove a mapping by name.

As part of this patch, the object type's wizard list was converted
from an ao2_container to an AST_VECTOR_RW.

A new test was added to test_sorcery for this capability.

ASTERISK-25044 #close

Change-Id: I9d2469a9296b2698082c0989e25e6848dc403b57