Update language in primitives intro (#3893)

Closes #3887 
We received feedback that one of the examples we give in the
introduction to primitives may imply that users have pulse-level access.
I've updated the language to center the examples around primitives as a
general computing concept.

---------

Co-authored-by: abbycross <[email protected]>

Author: kaelynj

docs/guides/primitives.ipynb

@@ -53,8 +53,7 @@
     "\n",
     "Computing systems are built on multiple layers of abstraction. Abstractions allow you to focus on a\n",
     "particular level of detail relevant to the task at hand. The closer you get to the hardware,\n",
-    "the lower the level of abstraction you need (for example, you might\n",
-    "want to manipulate electrical signals), and vice versa. The more complex the task you want to perform,\n",
+    "the lower the level of abstraction you need (for example, you might need to move or manipulate data at the CPU instruction level). The more complex the task you want to perform,\n",
     "the higher-level the abstractions will be (for example, you could be using a programming library to perform\n",
     "algebraic calculations).\n",
     "\n",