Update support dates for 3.16 and 3.15

Author: josh-wong

docs/releases/release-support-policy.mdx

@@ -30,16 +30,16 @@ This page describes Scalar's support policy for major and minor version releases
   <tbody>
     <tr>
       <td><a href="https://scalardb.scalar-labs.com/docs/latest/releases/release-notes#v3160">3.16</a></td>
-      <td>2025-06-20</td>
+      <td>2025-06-23</td>
       <td>TBD*</td>
       <td>TBD*</td>
       <td><a href="https://www.scalar-labs.com/contact">Contact us</a></td>
     </tr>
     <tr>
       <td><a href="https://scalardb.scalar-labs.com/docs/3.15/releases/release-notes#v3150">3.15</a></td>
       <td>2025-02-20</td>
-      <td>2026-06-20</td>
-      <td>2026-12-17</td>
+      <td>2026-06-23</td>
+      <td>2026-12-20</td>
       <td><a href="https://www.scalar-labs.com/contact">Contact us</a></td>
     </tr>
     <tr>

i18n/versioned_docs/ja-jp/docusaurus-plugin-content-docs/current/releases/release-support-policy.mdx

@@ -34,16 +34,16 @@ import TranslationBanner from '/src/components/_translation-ja-jp.mdx';
   <tbody>
     <tr>
       <td><a href="https://scalardb.scalar-labs.com/ja-jp/docs/latest/releases/release-notes#v3160">3.16</a></td>
-      <td>2025-02-20</td>
+      <td>2026-06-23</td>
       <td>TBD*</td>
       <td>TBD*</td>
       <td><a href="https://www.scalar-labs.com/contact">お問い合わせ</a></td>
     </tr>
     <tr>
       <td><a href="https://scalardb.scalar-labs.com/ja-jp/docs/3.15/releases/release-notes#v3150">3.15</a></td>
       <td>2025-02-20</td>
-      <td>2026-06-20</td>
-      <td>2026-12-17</td>
+      <td>2026-06-23</td>
+      <td>2026-12-20</td>
       <td><a href="https://www.scalar-labs.com/contact">お問い合わせ</a></td>
     </tr>
     <tr>