update specs links and title

Author: gareth-nx

doc/specs/stdlib_selection.md

@@ -131,7 +131,7 @@ end of this document shows that is the case.
     end program demo_select
 ```
 
-## `arg_select` - find the k-th smallest value in an input array
+## `arg_select` - find the index of the k-th smallest value in an input array
 
 ### Status
 

src/stdlib_selection.fypp

@@ -22,7 +22,7 @@ public select, arg_select
 
 interface select
     !! version: experimental
-    !! ([Specification](..//page/specs/stdlib_selection.html#description))
+    !! ([Specification](..//page/specs/stdlib_selection.html#select-find-the-k-th-smallest-value-in-an-input-array))
 
   #:for arraykind, arraytype in ARRAY_KINDS_TYPES
     #:for intkind, inttype in INT_KINDS_TYPES
@@ -34,7 +34,7 @@ end interface
 
 interface arg_select
     !! version: experimental
-    !! ([Specification](..//page/specs/stdlib_selection.html#description_1))
+    !! ([Specification](..//page/specs/stdlib_selection.html#arg_select-find-the-index-of-the-k-th-smallest-value-in-an-input-array))
   #:for arraykind, arraytype in ARRAY_KINDS_TYPES
     #:for intkind, inttype in INT_KINDS_TYPES
       #:set name = rname("arg_select", 1, arraytype, arraykind, intkind)