only fail on install, not build

setup.py

@@ -42,7 +42,7 @@
     url="https://github.com/dbt-labs/dbt-core",
     zip_safe=False,
     classifiers=[
-        'Development Status :: 5 - Production/Stable',
+        'Development Status :: 7 - Inactive',
 
         'License :: OSI Approved :: Apache Software License',
 
@@ -59,11 +59,12 @@
 )
 
 
-print('')
-print('As of v1.0.0, `pip install dbt` is no longer supported.')
-print('Instead, please use either:')
-print('  - `pip install dbt-core`, for core functionality')
-print('  - `pip install dbt-<adapter>`, to use dbt with your database, platform, or query engine')
-print('See full list: https://docs.getdbt.com/docs/available-adapters')
-print('')
-sys.exit(1)
+if 'sdist' not in sys.argv:
+    print('')
+    print('As of v1.0.0, `pip install dbt` is no longer supported.')
+    print('Instead, please use either:')
+    print('  - `pip install dbt-core`, for core functionality')
+    print('  - `pip install dbt-<adapter>`, to use dbt with your database, platform, or query engine')
+    print('See full list: https://docs.getdbt.com/docs/available-adapters')
+    print('')
+    sys.exit(1)