[stdlib] Don't make math.lcm take owned arguments

There's no need for `math.lcm` to take ownership of its arguments.
Remove the `owned` keyword so the default argument convention of
`borrowed` is used for the function arguments. This will also simplify
#3041.

MODULAR_ORIG_COMMIT_REV_ID: 782c1016c7fe287fc21115504e75098431fe80dd

stdlib/src/math/math.mojo

@@ -1997,7 +1997,7 @@ fn gcd(*values: Int) -> Int:
 # ===----------------------------------------------------------------------=== #
 
 
-fn lcm(owned m: Int, owned n: Int, /) -> Int:
+fn lcm(m: Int, n: Int, /) -> Int:
     """Computes the least common multiple of two integers.
 
     Args: