docs: remove trailing comma

Signed-off-by: Philipp Burckhardt <[email protected]>

Author: Planeshifter

lib/node_modules/@stdlib/stats/base/dists/planck/logcdf/README.md

@@ -161,7 +161,7 @@ for ( i = 0; i < lambda.length; i++ ) {
 Evaluates the logarithm of the [cumulative distribution function][cdf] for a Planck (discrete exponential) distribution with shape parameter `lambda`.
 
 ```c
-double out = stdlib_base_dists_planck_logcdf( 2, 0.5,);
+double out = stdlib_base_dists_planck_logcdf( 2, 0.5 );
 // returns ~-0.2525
 ```