Add support for BOM-signed env files

[hosni]

Fix #500

[hosni]

Some checks were not successful by GitHub actions runner, But I did not encounter this problem on the local system when run test command!

So, I run the test command more and more until I face the above problem!
I realized the problem is sometime the uuid function of PHP generates a UUID that is like Scientific Notation
For example: 61898400105e6 or 61898400105e7
And for unknown reason, PHP treated this string as int! (even with strict_types)
I put a var_dump to print the generated key and value pair, see:

Actually, I don't know why string is treated as int by PHP (even with strict_types)
But I think one of the solutions is to add a prefix to uuid method, something like: pdenv, But I don't know it is a correct solution for solve this or not!
See:

phpdotenv/tests/Dotenv/Repository/RepositoryTest.php

Line 54 in accaddf

$this->keyVal = [\uniqid() => \uniqid()];

[GrahamCampbell]

Thanks. 🍻