Optimizable items, about uploading attachments

[FJJ95]

Dapplo.Jira/src/Dapplo.Jira/AttachmentDomainExtensions.cs

Line 26 in 4958fe6

public static async Task<Attachment> AttachAsync<TContent>(this IAttachmentDomain jiraClient, string issueKey, TContent content, string filename,

Thanks for your help, it saved me a lot of time,
The following are only suggestions for optimizable items, not questions or denials.

As mentioned in the developer article, Jira's attachments can support multiple uploads, and I myself tried PostMan to call the API to test the results, So I think it is possible to support multiple files here, if we want to do.

https://developer.atlassian.com/cloud/jira/platform/rest/v2/api-group-issue-attachments/#api-rest-api-2-issue-issueidorkey-attachments-post