Uppercase git hashes are not transformed into links

Git handles the string representation of a commit hash regardless of the case but gitlab will not turn the upcase representations into links.

For example observe how this table is rendered:

| lowercase | uppercase |
|------------|------------|
| 45d8bc02374a | 45D8BC02374A |
lowercase uppercase
45d8bc02 45D8BC02374A
Edited by Basile.B