Assert a function output is greater than or equal to an expression.
Pseudocode: function(a) ≥ expr
use assertables::*; let a: i8 = -2; let b: i8 = 1; assert_fn_ge_expr!(i8::abs, a, b);
assert_fn_ge_expr
assert_fn_ge_expr_as_result
debug_assert_fn_ge_expr