Bump required stcal version to 0.5.1 (#6553)

Author: hbushouse

setup.cfg

@@ -43,7 +43,7 @@ install_requires =
     requests>=2.22
     scipy>=1.6.0
     spherical-geometry>=1.2.22
-    stcal>=0.5.0
+    stcal>=0.5.1
     stdatamodels>=0.3.0,<1.0
     stpipe>=0.3.1,<1.0
     stsci.image>=2.3.5