Update astropy requirement from <7,>=6.0 to >=6.0,<8

Updates the requirements on [astropy](https://github.com/astropy/astropy) to permit the latest version.
- [Release notes](https://github.com/astropy/astropy/releases)
- [Changelog](https://github.com/astropy/astropy/blob/main/docs/changelog.rst)
- [Commits](astropy/astropy@v6.0.0...v7.0.0)

---
updated-dependencies:
- dependency-name: astropy
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

pyproject.toml

@@ -20,7 +20,7 @@ classifiers = [
 ]
 dependencies = [
     "asdf>=3.1.0,<4",
-    "astropy>=6.0,<7",
+    "astropy>=6.0,<8",
     "astroquery>=0.4.7,<0.5.0",
     "beautifulsoup4>=4.12.3,<5",
     "bokeh>=3.4.0,<4",