Drop JDK 8 Support (#172)

* github/build: verify javadoc validity

* github/build: stop testing against JDK 8

* github/build: test against JDK 16 and 17-ea

Drop testing against JDK 15

* github/deploy: remove graphviz

* github.deploy: nexus username is not a secret

* github/settings: nexus username is not a secret

* github/deploy: publish javadoc

To: https://kemitix.github.io/wiser-assertions/

* github/build: upgrade setup-java action to 2.1.0

* github/deploy: upgrade setup-java action to 2.1.0

.github/settings.xml

@@ -3,12 +3,12 @@
     <servers>
         <server>
             <id>sonatype-nexus-snapshots</id>
-            <username>${env.NEXUS_USERNAME}</username>
+            <username>kemitix</username>
             <password>${env.NEXUS_PASSWORD}</password>
         </server>
         <server>
             <id>sonatype-nexus-staging</id>
-            <username>${env.NEXUS_USERNAME}</username>
+            <username>kemitix</username>
             <password>${env.NEXUS_PASSWORD}</password>
         </server>
     </servers>

.github/workflows/build-maven.yml

@@ -11,13 +11,15 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        java: [ 8, 11, 15 ]
+        java: [ 11, 16, 17-ea ]
     steps:
-      - uses: kamiazya/setup-graphviz@v1
       - uses: actions/checkout@v2
       - name: setup-jdk-${{ matrix.java }}
-        uses: actions/setup-java@v1
+        uses: actions/setup-java@v2.1.0
         with:
+          distribution: adopt
           java-version: ${{ matrix.java }}
       - name: build-jar
         run: mvn -B install
+      - name: verify javadoc
+        run: mvn -P release javadoc:javadoc

.github/workflows/deploy-sonatype.yml

@@ -9,11 +9,11 @@ jobs:
   deploy:
     runs-on: ubuntu-latest
     steps:
-      - uses: kamiazya/setup-graphviz@v1
       - uses: actions/checkout@v2
       - name: Set up JDK
-        uses: actions/setup-java@v1
+        uses: actions/setup-java@v2.1.0
         with:
+          distribution: adopt
           java-version: 8
       - name: Build with Maven
         run: mvn -B install
@@ -34,7 +34,11 @@ jobs:
             -B \
             deploy
         env:
-          NEXUS_USERNAME: ${{ secrets.NEXUS_USERNAME }}
           NEXUS_PASSWORD: ${{ secrets.NEXUS_PASSWORD }}
           GPG_KEYNAME: ${{ secrets.GPG_KEYNAME }}
           GPG_PASSPHRASE: ${{ secrets.GPG_PASSPHRASE }}
+      - name: Publish Javadoc
+        uses: JamesIves/github-pages-deploy-action@4.1.4
+        with:
+          branch: gh-pages # The branch the action should deploy to.
+          folder: target/apidocs # The folder the action should deploy.