Added close-figs context in discrete RV docstrings (#6301)

* added close-figs context

Author: hyosubkim

pymc/distributions/discrete.py

@@ -913,13 +913,14 @@ def rng_fn_scipy(cls, rng, lower, upper, size=None):
 
 
 class DiscreteUniform(Discrete):
-    R"""
-    Discrete uniform distribution.
+    R"""Discrete uniform distribution.
+
     The pmf of this distribution is
 
     .. math:: f(x \mid lower, upper) = \frac{1}{upper-lower+1}
 
     .. plot::
+        :context: close-figs
 
         import matplotlib.pyplot as plt
         import numpy as np
@@ -946,9 +947,9 @@ class DiscreteUniform(Discrete):
 
     Parameters
     ----------
-    lower: int
+    lower : tensor_like of int
         Lower limit.
-    upper: int
+    upper : tensor_like of int
         Upper limit (upper > lower).
     """
 
@@ -997,6 +998,7 @@ class Categorical(Discrete):
     .. math:: f(x \mid p) = p_x
 
     .. plot::
+        :context: close-figs
 
         import matplotlib.pyplot as plt
         import numpy as np
@@ -1267,6 +1269,7 @@ class ZeroInflatedBinomial:
             \end{array} \right.
 
     .. plot::
+        :context: close-figs
 
         import matplotlib.pyplot as plt
         import numpy as np
@@ -1342,6 +1345,7 @@ class ZeroInflatedNegativeBinomial:
        \right.
 
     .. plot::
+        :context: close-figs
 
         import matplotlib.pyplot as plt
         import numpy as np