ci: remove Java 18 build

Siroshun09 · Siroshun09 · commit 6895b4385b2d · 2022-07-09T22:00:09.000+09:00
diff --git a/.github/workflows/maven.yml b/.github/workflows/maven.yml
@@ -10,7 +10,3 @@ jobs:
     uses: okocraft/workflows/.github/workflows/maven.yml@v1
     with:
       java-version: '17'
-  build-java-18:
-    uses: okocraft/workflows/.github/workflows/maven.yml@v1
-    with:
-      java-version: '18'
