remove: remove dnanmean from namespace

This commit removes the `dnanmean` symbol from the `@stdlib/stats/base`
namespace due to a package migration.

BREAKING CHANGE: remove `dnanmean`

To migrate, users should access the same symbol via the
`@stdlib/stats/strided` namespace.

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type: pre_commit_static_analysis_report
description: Results of running static analysis checks when committing changes.
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---

Author: aayush0325

lib/node_modules/@stdlib/stats/base/lib/index.js

@@ -171,15 +171,6 @@ setReadOnly( ns, 'dmskmin', require( '@stdlib/stats/base/dmskmin' ) );
 */
 setReadOnly( ns, 'dmskrange', require( '@stdlib/stats/base/dmskrange' ) );
 
-/**
-* @name dnanmean
-* @memberof ns
-* @readonly
-* @type {Function}
-* @see {@link module:@stdlib/stats/base/dnanmean}
-*/
-setReadOnly( ns, 'dnanmean', require( '@stdlib/stats/base/dnanmean' ) );
-
 /**
 * @name dnanmeanors
 * @memberof ns