Corrected doc/specs/incex,md

Changed `[sorting](.stdlib_sorting.md)` to `[sorting](./stdlib_sorting.md)`

[ticket: X]

Author: wclodius2

doc/specs/index.md

@@ -19,7 +19,7 @@ This is and index/directory of the specifications (specs) for each new module/fe
  - [logger](./stdlib_logger.html) - Runtime logging system
  - [optval](./stdlib_optval.html) - Fallback value for optional arguments
  - [quadrature](./stdlib_quadrature.html) - Numerical integration
- - [sorting](.stdlib_sorting.html) - Sorting of rank one arrays
+ - [sorting](./stdlib_sorting.html) - Sorting of rank one arrays
  - [stats](./stdlib_stats.html) - Descriptive Statistics
  - [stats_distribution_PRNG](./stdlib_stats_distribution_PRNG.html) - Probability Distributions random number generator
  - [string\_type](./stdlib_string_type.html) - Basic string support