langref: incorrect use of the term "enum variant" in enums.zig

[gettsu]

Closes #13838

[ghost]

There's a third place it's used on line 3587:

// Declare a specific instance of the enum variant.
const c = Type.ok;

[perillo]

In commit 68d0474, I think enum element should be replaced with enum field.

[gettsu]

In commit 68d0474, I think enum element should be replaced with enum field.

Thank you! I've fixed this!