% (as part of the file name) is not supported

[pillsilly]

on https://stackblitz.com/edit/ngx-filesaver ,
it's reproducible if you add a % in line 56

no error prompted, no uncaught exception, no nothing.

Also I tested the FileSaver implementation it's supported.

[cipchk]

Because ngx-filesaver used of URL parsing, so you can use:

- const fileName = `save%.${type}`;
+ const fileName = encodeURI(`save%.${type}`);

to fixed this.

[pillsilly]

Because ngx-filesaver used of URL parsing, so you can use:

- const fileName = `save%.${type}`;
+ const fileName = encodeURI(`save%.${type}`);

to fixed this.

Thanks for the hint,
what about including the encodeURI work inside the lib so that to clients it'll be much more intuitive?
If it sounds ok then I am ok providing PR.