Numeric less-than-or-equal assertion
Passes if a <= b for numeric arguments (Int or
Float).
a (Int): | Float The left-hand
numeric value.
b (Int): | Float The right-hand
numeric value.
Expect_pass when a <= b,
Expect_stop otherwise.
assert(expect_lte(1, 1))
assert(expect_lte(1, 2))