fix: change example in readme

Author: 0PrashantYadav0

lib/node_modules/@stdlib/stats/base/dists/geometric/pmf/README.md

@@ -168,8 +168,8 @@ for ( i = 0; i < 10; i++ ) {
 Evaluates evaluating the [probability mass function][pmf] (PMF) of a [geometric][geometric-distribution] distribution with success probability `0 <= p <= 1`.
 
 ```c
-double out = stdlib_base_dists_geometric_pmf( 2.0, 0.5 );
-// returns 0.875
+double out = stdlib_base_dists_geometric_pmf( 4.0, 0.3 );
+// returns ~0.072
 ```
 
 The function accepts the following arguments: