feat: add invgamma and betaprime to namespace

Author: kgryte

lib/node_modules/@stdlib/random/array/lib/index.js

@@ -90,6 +90,15 @@ setReadOnly( ns, 'exponential', require( '@stdlib/random/array/exponential' ) );
 */
 setReadOnly( ns, 'gamma', require( '@stdlib/random/array/gamma' ) );
 
+/**
+* @name invgamma
+* @memberof ns
+* @readonly
+* @type {Function}
+* @see {@link module:@stdlib/random/array/invgamma}
+*/
+setReadOnly( ns, 'invgamma', require( '@stdlib/random/array/invgamma' ) );
+
 /**
 * @name lognormal
 * @memberof ns