docs: correct spelling in Gate Zoo notebook (#8378)

Corrected two spelling errors in the Gate Zoo notebook. Change “radiants
abougt” to “radians about.”

Author: SteveSonyJacob

docs/gatezoo.ipynb

@@ -128,7 +128,7 @@
    "source": [
     "### Traditional Pauli Rotation Gates\n",
     "\n",
-    "Cirq defines traditional single qubit rotations that are rotations in radiants abougt different Pauli directions."
+    "Cirq defines traditional single qubit rotations that are rotations in radians about different Pauli directions."
    ]
   },
   {