Clear out requirements-sdp.txt for post-B7.6 regression testing (#5362)

* Clean out requirements-sdp.txt post-B7.6

* Update LICENSE file to 2020 date

LICENSE

@@ -1,4 +1,4 @@
-Copyright (C) 2010 Association of Universities for Research in Astronomy (AURA)
+Copyright (C) 2020 Association of Universities for Research in Astronomy (AURA)
 
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are met:

requirements-sdp.txt

@@ -3,49 +3,3 @@
 #     pip install -e .[test]
 #     pip install pytest-xdist
 #     pip freeze | grep -v jwst.git >> requirements-sdp.txt
-asdf==2.7.1
-astropy==4.0.1.post1
-attrs==19.3.0
-certifi==2020.6.20
-chardet==3.0.4
-ci-watson==0.5
-codecov==2.1.8
-coverage==5.2.1
-crds==7.6.0
-Cython==0.29.21
-drizzle==1.13.1
-filelock==3.0.12
-gwcs==0.14.0
-idna==2.10
-importlib-metadata==1.7.0
-jsonschema==3.2.0
-lxml==4.5.2
-more-itertools==8.4.0
-numpy==1.19.1
-packaging==20.4
-Parsley==1.3
-photutils==0.7.2
-pluggy==0.13.1
-psutil==5.7.2
-py==1.9.0
-pyparsing==2.4.7
-pyrsistent==0.16.0
-pytest==5.4.3
-pytest-cov==2.10.0
-pytest-doctestplus==0.8.0
-pytest-openfiles==0.5.0
-pytest-xdist==1.34.0
-PyYAML==5.3.1
-requests==2.24.0
-requests-mock==1.8.0
-scipy==1.5.2
-semantic-version==2.8.5
-six==1.15.0
-spherical-geometry==1.2.18
-stsci.image==2.3.3
-stsci.imagestats==1.6.2
-stsci.stimage==0.2.4
-tweakwcs==0.6.4
-urllib3==1.25.10
-wcwidth==0.2.5
-zipp==3.1.0