Remove "unmaintained" banner for 2.5.0 (redhat-developer#5884)

**What type of PR is this:**

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/kind documentation

**What does this PR do / why we need it:**

Removes the "unmaintained" part of website when it refers to 2.5.0

**Which issue(s) this PR fixes:**
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N/A

**How to test changes / Special notes to the reviewer:**

Signed-off-by: Charlie Drage <[email protected]>

docs/website/docusaurus.config.js

@@ -129,10 +129,13 @@ module.exports = {
             current: {
               label: '3.0.0 (Alpha 2) 🚧',
               badge: true,
+              banner: 'none',
             },
             '2.5.0': {
               label: '2.5.0 (Stable) 🚀',
               path: '2.5.0',
+              badge: true,
+              banner: 'none',
             },
           },
           sidebarPath: require.resolve('./sidebars.js'),