Feature Request: Support for remote attachments

Hello,

I am using `Allure.Reqnroll`.

## Steps to reproduce

Run the following code:

```cs
AllureApi.AddAttachment(
"Video Recording",
"video/mp4",
"https://www.browserstack.com/some-video.mp4"
);
```

## Expected outcome

The video is not downloaded but playable in the report

## Actual outcome

Received the following error:

```
System.IO.IOException : The filename, directory name, or volume label syntax is incorrect. : 'C:\my-project\bin\Debug\net8.0\https:\www.browserstack.com\some-video.mp4'
```

## Additional notes

I also tried this:

```
var attachment = new Attachment
{
name = "Video Recording",
type = "video/mp4",
source = "https://www.browserstack.com/some-video.mp4"
};
AllureLifecycle.Instance.UpdateExecutableItem(
delegate(ExecutableItem item)
{
item.attachments.Add(attachment);
}
);
```

It worked! When I ran `allure generate` though I got the following error:

```
Exception in thread "main" java.nio.file.InvalidPathException: Illegal char <:> at index 5: https://www.browserstack.com/some-video.mp4
at java.base/sun.nio.fs.WindowsPathParser.normalize(WindowsPathParser.java:182)
at java.base/sun.nio.fs.WindowsPathParser.parse(WindowsPathParser.java:153)
at java.base/sun.nio.fs.WindowsPathParser.parse(WindowsPathParser.java:77)
at java.base/sun.nio.fs.WindowsPath.parse(WindowsPath.java:92)
at java.base/sun.nio.fs.WindowsFileSystem.getPath(WindowsFileSystem.java:232)
at java.base/java.nio.file.Path.resolve(Path.java:515)
at io.qameta.allure.allure2.Allure2Plugin.convert(Allure2Plugin.java:267)
at io.qameta.allure.allure2.Allure2Plugin.lambda$convert$10(Allure2Plugin.java:232)
at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:179)
at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1625)
at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)
at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)
at java.base/java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:921)
at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
at java.base/java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:682)
at io.qameta.allure.util.ConvertUtils.convertList(ConvertUtils.java:45)
at io.qameta.allure.util.ConvertUtils.convertList(ConvertUtils.java:36)
at io.qameta.allure.allure2.Allure2Plugin.convert(Allure2Plugin.java:232)
at io.qameta.allure.allure2.Allure2Plugin.lambda$processStages$5(Allure2Plugin.java:159)
at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1625)
at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)
at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)
at java.base/java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:921)
at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
at java.base/java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:682)
at io.qameta.allure.allure2.Allure2Plugin.processStages(Allure2Plugin.java:160)
at io.qameta.allure.allure2.Allure2Plugin.lambda$readResults$1(Allure2Plugin.java:122)
at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:183)
at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:179)
at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:179)
at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1625)
at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)
at java.base/java.util.stream.ForEachOps$ForEachTask.compute(ForEachOps.java:290)
at java.base/java.util.concurrent.CountedCompleter.exec(CountedCompleter.java:754)
at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:373)
at java.base/java.util.concurrent.ForkJoinTask.invoke(ForkJoinTask.java:686)
at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateParallel(ForEachOps.java:159)
at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateParallel(ForEachOps.java:173)
at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:233)
at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:596)
at io.qameta.allure.allure2.Allure2Plugin.readResults(Allure2Plugin.java:121)
at io.qameta.allure.ReportGenerator.lambda$readResults$0(ReportGenerator.java:55)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
at io.qameta.allure.ReportGenerator.readResults(ReportGenerator.java:55)
at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:179)
at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1625)
at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)
at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)
at java.base/java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:921)
at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
at java.base/java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:682)
at io.qameta.allure.ReportGenerator.generate(ReportGenerator.java:120)
at io.qameta.allure.ReportGenerator.generate(ReportGenerator.java:103)
at io.qameta.allure.Commands.generate(Commands.java:146)
at io.qameta.allure.Commands.generate(Commands.java:174)
at io.qameta.allure.CommandLine.run(CommandLine.java:160)
at java.base/java.util.Optional.orElseGet(Optional.java:364)
at io.qameta.allure.CommandLine.main(CommandLine.java:92)
```

Start at AllureApi.AddAttachment and the Attachment path used with UpdateExecutableItem, then trace how the attachment is handled by allure generate and the Allure2Plugin.convert entry point shown in the stack trace. Done means a remote video URL remains playable in the generated report without being treated as a local Windows path.

Written by the indexing model from the issue text.