bench: refactor to use dynamic memory allocation at number/uint8/base/mul native

---
type: pre_commit_static_analysis_report
description: Results of running static analysis checks when committing changes.
report:
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    status: passed
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    status: passed
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    status: na
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    status: missing_dependencies
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---

Author: piyxsh31

lib/node_modules/@stdlib/number/uint8/base/mul/benchmark/c/native/benchmark.c

@@ -91,12 +91,13 @@ static double rand_double( void ) {
 * @return elapsed time in seconds
 */
 static double benchmark( void ) {
-	uint8_t x[ 100 ];
+	uint8_t *x;
 	double elapsed;
 	uint8_t y;
 	double t;
 	int i;
 
+	x = (uint8_t *) malloc( 100 * sizeof( uint8_t ) );
 	for ( i = 0; i < 100; i++ ) {
 		x[ i ] = (uint8_t)( 2.0*rand_double() ) + 10;
 	}
@@ -113,6 +114,7 @@ static double benchmark( void ) {
 	if ( y > 100 ) {
 		printf( "unexpected value\n" );
 	}
+	free( x );
 	return elapsed;
 }