fix location issue for VisibilityDeclaration

[lucica28]

The issue is that right now the location for VisibilityDeclaration is the location of the next token after the access specifier. Example
private
{
....

And let's say private is on line 1. The location of the VisibilityDeclaration will store 2 as the line number (the line number of '{' ), which is not correct

[dlang-bot]

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[thewilsonator]

Test?

[RazvanN7]

@lucica28 please add a test for this.