fetch-issues: Use Jira Cloud API v2 instead of v3

The Atlassian API documentation for Jira Cloud describes the difference
between version 2 and version 3:

> This documentation is for version 3 of the Jira Cloud platform REST
> API, which is the latest version but is in beta. Version 2 and version
> 3 of the API offer the same collection of operations. However, version
> 3 provides support for the Atlassian Document Format (ADF) in:
>
> * body in comments, including where comments are used in issue, issue
>   link, and transition resources.
> * comment in worklogs.
> * description and environment fields in issues.
> * textarea type custom fields (multi-line text fields) in issues.
>   Single line custom fields (textfield) accept a string and don't handle
>   Atlassian Document Format content.
>
> However, these new features are under development and may change.

https://developer.atlassian.com/cloud/jira/platform/rest/v3/intro/#version

The Atlassian Document Format referenced is described in JSON. Here is
an excerpt of an issue description in the format:

    "description": {
      "version": 1,
      "type": "doc",
      "content": [
        {
          "type": "heading",
          "attrs": {
            "level": 2
          },
          "content": [
            {
              "type": "text",
              "text": "Context"
            }
          ]
        },
        {
          "type": "paragraph",
          "content": [
            {
              "type": "text",

That format would make it much harder to get an issue's description text
for easy inclusion in an email. Fortunately, we can switch to version 2
of the Cloud API with no loss of functionality, and get a plain text
description suitable for inclusion in an email message.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/main.lisp b/src/main.lisp
index 0c78c99..d15ab6e 100644
--- a/src/main.lisp
+++ b/src/main.lisp
@@ -57,7 +57,7 @@
 
 (defun fetch-issues (endpoint jql start-at &key basic-auth-token)
   (jzon:parse
-    (dex:post (format nil "https://~A/rest/api/3/search" endpoint)
+    (dex:post (format nil "https://~A/rest/api/2/search" endpoint)
               :content
               (jzon:stringify
                 `((:jql . ,jql)