[MC-121737] /tag list command feedback says "tags" even if target has only one tag

The bug

The command feedback of the /tag <targets> list command says "tags" even if the target has only one. Same for the summary in case <targets> matches multiple entities. Expected would be "tag(s)" instead.

How to reproduce

Use the following command
```
/tag @s add test
```
→ "Added tag 'test' to <target>"
Use the following command
```
/tag @s list
```
→ "<targets> has 1 tags: test"

Respectively "The <count> entities have 1 total tags: test"