docs: update return value and remove unused header in geometric median README

Author: unas0706

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

@@ -154,7 +154,7 @@ Returns the [median][median] of a [geometric][geometric-distribution] distributi
 
 ```c
 double out = stdlib_base_dists_geometric_median( 0.5 );
-// returns 1
+// returns 0
 ```
 
 The function accepts the following arguments:
@@ -184,7 +184,6 @@ double stdlib_base_dists_geometric_median( const double p );
 ### Examples
 
 ```c
-#include "stdlib/stats/base/dists/geometric/median.h"
 #include <stdlib.h>
 #include <stdio.h>
 #include <math.h>