tests/basic: Make various tests skippable.

tests/basics/bytes_add_array.py

@@ -0,0 +1,12 @@
+# test bytes + other
+try:
+    import array
+except ImportError:
+    import sys
+    print("SKIP")
+    sys.exit()
+
+# should be byteorder-neutral
+print(b"123" + array.array('h', [0x1515]))
+
+print(b"\x01\x02" + array.array('b', [1, 2]))