Remove file_url replacement trailing slash

[Aerzas]

To support protocol relative URLs, a slash is added after the replacement but it introduces multiple issues.

When the baseUrl is defined to a domain, it adds an unecessary slash.

• Base Url: http://example.test/
• URL: stream://image/dummy.png
• URL replaced: http://example.test//image/dummy.png

When the baseUrl is not defined, it adds an unecessary leading slash.

• Base Url: /
• URL: stream://image/dummy.png
• URL replaced: //image/dummy.png

Note that //image/dummy.png is not a valid protocal-relative URL since there is no domain, a correct URL would be//example.test/image/dummy.png

[Aerzas]

It seems to happen only when the stream wrapper is mapped to an empty string (during development).