Don't auto download IERS during testing

sunpy/conftest.py

@@ -7,6 +7,8 @@
 
 import astropy
 import astropy.config.paths
+import astropy.io.fits
+from astropy.utils import iers
 
 from sunpy.util import SunpyUserWarning
 
@@ -39,6 +41,17 @@ def jsoc_test_email():
     return "nabil.freij@gmail.com"
 
 
+@pytest.fixture(scope='session', autouse=True)
+def no_download_iers(request):
+    # Don't try and download IERS during tests
+    # See https://github.com/astropy/astropy/issues/12998 for issue that this
+    # sidesteps
+    old_value = iers.conf.auto_download
+    iers.conf.auto_download = False
+    yield
+    iers.conf.auto_download = old_value
+
+
 @pytest.fixture(scope='session', autouse=True)
 def tmp_config_dir(request):
     """