UDAs with single template argument are sandwiched with declaration

[Dennis]

Input:

@1 float f() => 1.0;

@"test name" unittest 
{
}

Expected output: the same
Actual dfmt output:

@1float f() => 1.0;

@"test name"unittest
{
}

The spaces after the attributes are removed, leading to code that looks worse or won't even compile anymore if you're unlucky.