Help: Fix typo in find_package documentation

Help/command/find_package.rst

@@ -59,7 +59,7 @@ for finding the package, checking the version, and producing any needed
 messages.  Some find-modules provide limited or no support for versioning;
 check the module documentation.
 
-If the ``MODULE`` option is not specfied in the above signature,
+If the ``MODULE`` option is not specified in the above signature,
 CMake first searches for the package using Module mode. Then, if the
 package is not found, it searches again using Config mode. A user
 may set the variable :variable:`CMAKE_FIND_PACKAGE_PREFER_CONFIG` to