docs: add C APIs section and related packages information to README

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Author: 0PrashantYadav0

lib/node_modules/@stdlib/stats/base/snanmeanwd/README.md

@@ -174,6 +174,22 @@ console.log( v );
 
 <!-- C usage documentation. -->
 
+* * *
+
+<section class="c">
+
+## C APIs
+
+<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->
+
+<section class="intro">
+
+</section>
+
+<!-- /.intro -->
+
+<!-- C usage documentation. -->
+
 <section class="usage">
 
 ### Usage
@@ -273,6 +289,10 @@ int main( void ) {
 
 <!-- /.c -->
 
+<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->
+
+<section class="related">
+
 * * *
 
 <section class="references">

lib/node_modules/@stdlib/stats/base/snanmeanwd/test/test.snanmeanwd.native.js

@@ -195,7 +195,7 @@ tape( 'the function supports a `stride` parameter', opts, function test( t ) {
 		NaN   // 4
 	]);
 
-	v = snanmeanwd( 4, x, 2 );
+	v = snanmeanwd( 5, x, 2 );
 
 	t.strictEqual( v, 1.25, 'returns expected value' );
 	t.end();
@@ -217,7 +217,7 @@ tape( 'the function supports a negative `stride` parameter', opts, function test
 		NaN   // 0
 	]);
 
-	v = snanmeanwd( 4, x, -2 );
+	v = snanmeanwd( 5, x, -2 );
 
 	t.strictEqual( v, 1.25, 'returns expected value' );
 	t.end();