tests/extmod/uhashlib_sha1: Coverage for SHA1 algorithm.

tests/extmod/uhashlib_sha1.py

+import sys
+try:
+    import uhashlib as hashlib
+except ImportError:
+    try:
+        import hashlib
+    except ImportError:
+        # This is neither uPy, nor cPy, so must be uPy with
+        # uhashlib module disabled.
+        print("SKIP")
+        sys.exit()
+
+try:
+    hashlib.sha1
+except AttributeError:
+    # SHA1 is only available on some ports
+    print("SKIP")
+    sys.exit()
+
+sha1 = hashlib.sha1(b'hello')
+sha1.update(b'world')
+print(sha1.digest())