Avoid `[]` parameters, prefer `span`

Reason

An array decays to a pointer, thereby losing its size, opening the opportunity for range errors. Use span to preserve size information.

Example

void f(int[]);          // not recommended

void f(int*);           // not recommended for multiple objects
                        // (a pointer should point to a single object, do not subscript)

void f(gsl::span<int>); // good, recommended

Enforcement

Flag [] parameters. Use span instead.