In preparation for upcoming changes to `deno install` in Deno 2.
If `-g` or `--global` flag is not provided a warning will be emitted:
```
⚠️ `deno install` behavior will change in Deno 2. To preserve the current behavior use `-g` or `--global` flag.
```
The same will happen for `deno uninstall` - unless `-g`/`--global` flag
is provided
a warning will be emitted.
Towards https://github.com/denoland/deno/issues/23062
---------
Signed-off-by: Bartek Iwańczuk <biwanczuk@gmail.com>
Co-authored-by: David Sherret <dsherret@users.noreply.github.com>