pages/donate: Remove reference to Plasma 6 for supporting members
Since we're continuing the campaign indefinitely, let's refer to them as just "Supporting Members".
| Page | Before | After |
|---|---|---|
| Donate |  |
 |
| Supporters |  |
 |
Since we're continuing the campaign indefinitely, let's refer to them as just "Supporting Members".
| Page | Before | After |
|---|---|---|
| Donate | |
|
| Supporters | |
|