test: add indefinite articles across blas/base/ndarray/*axpy test descriptions

Propagates fix from d4c1b8b1a ("test: update description") and b8ad692
("test: update description") to sibling axpy packages — inserting missing
"a " before "one-dimensional ndarray `x`" and "one-dimensional ndarray `y`"
in the top-level tape() description. Affects `gaxpy`, `saxpy`, `daxpy`.

https://claude.ai/code/session_01GXZT2uLjX36Q2EepAt4GeQ

Author: claude

lib/node_modules/@stdlib/blas/base/ndarray/daxpy/test/test.js

@@ -59,7 +59,7 @@ tape( 'the function has an arity of 1', function test( t ) {
 	t.end();
 });
 
-tape( 'the function multiplies one-dimensional ndarray `x` by a constant `alpha` and adds the result to one-dimensional ndarray `y`', function test( t ) {
+tape( 'the function multiplies a one-dimensional ndarray `x` by a constant `alpha` and adds the result to a one-dimensional ndarray `y`', function test( t ) {
 	var expected;
 	var alpha;
 	var xbuf;

lib/node_modules/@stdlib/blas/base/ndarray/gaxpy/test/test.js

@@ -58,7 +58,7 @@ tape( 'the function has an arity of 1', function test( t ) {
 	t.end();
 });
 
-tape( 'the function multiplies one-dimensional ndarray `x` by a constant `alpha` and adds the result to one-dimensional ndarray `y`', function test( t ) {
+tape( 'the function multiplies a one-dimensional ndarray `x` by a constant `alpha` and adds the result to a one-dimensional ndarray `y`', function test( t ) {
 	var expected;
 	var alpha;
 	var xbuf;

lib/node_modules/@stdlib/blas/base/ndarray/saxpy/test/test.js

@@ -59,7 +59,7 @@ tape( 'the function has an arity of 1', function test( t ) {
 	t.end();
 });
 
-tape( 'the function multiplies one-dimensional ndarray `x` by a constant `alpha` and adds the result to one-dimensional ndarray `y`', function test( t ) {
+tape( 'the function multiplies a one-dimensional ndarray `x` by a constant `alpha` and adds the result to a one-dimensional ndarray `y`', function test( t ) {
 	var expected;
 	var alpha;
 	var xbuf;