fix minor error in notebook to generate images for README

Author: drbenvincent

docs/notebooks/generate_plots.ipynb

@@ -242,7 +242,7 @@
    "source": [
     "fig, ax = result.plot()\n",
     "plt.savefig(\n",
-    "    \"../../img/difference_in_differences_pymc\", bbox_inches=\"tight\", pad_inches=0.1\n",
+    "    \"../../img/difference_in_differences_pymc.svg\", bbox_inches=\"tight\", pad_inches=0.1\n",
     ")"
    ]
   },
@@ -363,7 +363,7 @@
    "source": [
     "fig, ax = result.plot()\n",
     "plt.savefig(\n",
-    "    \"../../img/regression_discontinuity_pymc\", bbox_inches=\"tight\", pad_inches=0.1\n",
+    "    \"../../img/regression_discontinuity_pymc.svg\", bbox_inches=\"tight\", pad_inches=0.1\n",
     ")"
    ]
   },
@@ -484,7 +484,7 @@
    ],
    "source": [
     "fig, ax = result.plot(plot_predictors=True)\n",
-    "plt.savefig(\"../../img/synthetic_control\", bbox_inches=\"tight\", pad_inches=0.1)"
+    "plt.savefig(\"../../img/synthetic_control_pymc.svg\", bbox_inches=\"tight\", pad_inches=0.1)"
    ]
   },
   {