fix(async/if-then): replace new Array() with array literal to satisfy lint rule

---
type: pre_commit_static_analysis_report
description: Results of running static analysis checks when committing changes.
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  - task: lint_filenames
    status: passed
  - task: lint_editorconfig
    status: passed
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    status: na
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    status: na
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    status: na
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    status: passed
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    status: na
  - task: lint_c_src
    status: na
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    status: na
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    status: passed
---

Author: t-sibiraj

lib/node_modules/@stdlib/utils/async/if-then/lib/main.js

@@ -119,10 +119,9 @@ function ifthenAsync( predicate, x, y, done ) {
 			return done( error );
 		}
 		nargs = arguments.length;
-		args = new Array( nargs );
-		args[ 0 ] = null;
+		args = [ null ];
 		for ( i = 1; i < nargs; i++ ) {
-			args[ i ] = arguments[ i ];
+			args.push(arguments[ i ]);
 		}
 		done.apply( null, args );
 	}