docs: apply suggestions from code review

Signed-off-by: Muhammad Haris <[email protected]>

Author: headlessNode

lib/node_modules/@stdlib/blas/ext/base/ndarray/gfind-index/README.md

@@ -115,8 +115,8 @@ var count = ctx.count;
 
 ## Notes
 
-- If provided an empty one-dimensional ndarray, the function returns `-1`.
-- A provided callback function should return a boolean value.
+-  If provided an empty one-dimensional ndarray, the function returns `-1`.
+-  A provided callback function should return a boolean value.
 
 </section>