fix(literals): move reference link into admonition (#856)

* fix(literals): move reference link into admonition

Special blocks (admonitions) are rendered by themselves without
including the rest of the page. Therefore, a reference link from the bottom of the
file is unavailable and cannot be resolved properly. This is
fixed by moving it to the bottom of the block instead of the bottom of
the file.

* fix(literals): remove non-existent `d` suffix

concepts/literals/about.md

@@ -36,7 +36,7 @@ This is a good default case and use-cases with the narrower `float` type are les
 ```cpp
 auto light_year_in_m{9.46073e+15f}; // well in the range of float
 auto earth_to_edge_comoving_distance_in_nm{4.32355e+32}; // needs double type for magnitude
-auto eulers_number{2.718281828459045d}; // needs double type for precision
+auto eulers_number{2.718281828459045}; // needs double type for precision
 ```
 
 ~~~~exercism/advanced
@@ -68,8 +68,9 @@ auto il_nam{"보는 것이 하는 것보다 더 재미있을 수가 없지"sv};
 
 A _string_view_ can be seen as a reference to a const string.
 
+[ascii-code]: https://www.ascii-code.com/
+
 ~~~~
 
 [numbers-concept]: https://exercism.org/tracks/cpp/concepts/numbers
 [in-depth-integers]: https://www.learncpp.com/cpp-tutorial/fixed-width-integers-and-size-t/
-[ascii-code]: https://www.ascii-code.com/

concepts/literals/introduction.md

@@ -36,7 +36,7 @@ This is a good default case and use-cases with the narrower `float` type are les
 ```cpp
 auto light_year_in_m{9.46073e+15f}; // well in the range of float
 auto earth_to_edge_comoving_distance_in_nm{4.32355e+32}; // needs double type for magnitude
-auto eulers_number{2.718281828459045d}; // needs double type for precision
+auto eulers_number{2.718281828459045}; // needs double type for precision
 ```
 
 ~~~~exercism/advanced
@@ -68,8 +68,9 @@ auto il_nam{"보는 것이 하는 것보다 더 재미있을 수가 없지"sv};
 
 A _string_view_ can be seen as a reference to a const string.
 
+[ascii-code]: https://www.ascii-code.com/
+
 ~~~~
 
 [numbers-concept]: https://exercism.org/tracks/cpp/concepts/numbers
 [in-depth-integers]: https://www.learncpp.com/cpp-tutorial/fixed-width-integers-and-size-t/
-[ascii-code]: https://www.ascii-code.com/