Cache title does not support UTF8 emoji

[andrixnet]

I was trying to edit a cache with an emoji in the titles, taken from https://emojipedia.org
I can paste the emoji in the title field, but upon saving, it dissapears.

[stefopl]

In my local environment, attempting the following SQL query:
UPDATE ocpl.caches t SET t.name = 'emoji Test 🔥' WHERE t.cache_id = 86263;
resulted in the error:
[2023-10-01 00:55:06] [HY000][1366] Incorrect string value: '\xF0\x9F\x94\xA5' for column 'name' at row 1
To resolve this, I executed:
alter table caches modify name varchar(255) collate utf8mb4_general_ci null;
After this change, the database worked correctly. However, on the webpage, it displayed emoji Test ?.
I solved this problem by modifying:
src/Utils/Database/OcPdo.php:35
'charset' => 'utf8' to: 'charset' => 'utf8mb4'

This is just a suggestion. It needs to be thoroughly tested

[deg-pl]

Related with #1681