Add test_11g_ojdbc11 workflow with Oracle JDK 21

Add a dedicated workflow exercising ruby-plsql against Oracle 11g XE
on JRuby 10.0.5.0 with ojdbc11.jar, modeled after the
test_11g_ojdbc11 workflow in oracle-enhanced. This keeps ojdbc11
coverage now that the main `test` and `test_11g` workflows have
moved to ojdbc17.

Pin Oracle JDK 21 via actions/setup-java since ojdbc11.jar is
certified with JDK 11 and JDK 21 per Oracle's JDBC downloads page,
and JRuby 10 itself requires Java 21.

Author: yahonda

.github/workflows/test_11g_ojdbc11.yml

@@ -0,0 +1,94 @@
+name: test_11g_ojdbc11
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    types: [opened, synchronize, reopened, ready_for_review]
+
+jobs:
+  build:
+    if: github.event_name != 'pull_request' || !github.event.pull_request.draft
+
+    runs-on: ubuntu-latest
+    continue-on-error: true
+    strategy:
+      matrix:
+        ruby: [
+          'jruby-10.0.5.0'
+        ]
+    env:
+      ORACLE_HOME: /opt/oracle/instantclient_21_15
+      LD_LIBRARY_PATH: /opt/oracle/instantclient_21_15
+      NLS_LANG: AMERICAN_AMERICA.AL32UTF8
+      TNS_ADMIN: ./ci/network/admin
+      DATABASE_NAME: XE
+      TZ: Europe/Riga
+      DATABASE_SYS_PASSWORD: Oracle18
+
+    services:
+      oracle:
+        image: gvenzl/oracle-xe:11
+        ports:
+          - 1521:1521
+        env:
+          TZ: Europe/Riga
+          ORACLE_PASSWORD: Oracle18
+        options: >-
+          --health-cmd healthcheck.sh
+          --health-interval 10s
+          --health-timeout 5s
+          --health-retries 10
+
+    steps:
+    - uses: actions/checkout@v6
+    - name: Set up Java
+      uses: actions/setup-java@v4
+      with:
+        distribution: oracle
+        java-version: '21'
+    - name: Set up Ruby
+      uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: ${{ matrix.ruby }}
+    - name: Create symbolic link for libaio library compatibility
+      run: |
+        sudo ln -s /usr/lib/x86_64-linux-gnu/libaio.so.1t64 /usr/lib/x86_64-linux-gnu/libaio.so.1
+    - name: Download Oracle instant client
+      run: |
+        wget -q https://download.oracle.com/otn_software/linux/instantclient/2115000/instantclient-basic-linux.x64-21.15.0.0.0dbru.zip
+        wget -q https://download.oracle.com/otn_software/linux/instantclient/2115000/instantclient-sqlplus-linux.x64-21.15.0.0.0dbru.zip
+        wget -q https://download.oracle.com/otn_software/linux/instantclient/2115000/instantclient-sdk-linux.x64-21.15.0.0.0dbru.zip
+    - name: Install Oracle instant client
+      run: |
+        sudo mkdir -p /opt/oracle/
+        sudo unzip -q instantclient-basic-linux.x64-21.15.0.0.0dbru.zip -d /opt/oracle
+        sudo unzip -qo instantclient-sqlplus-linux.x64-21.15.0.0.0dbru.zip -d /opt/oracle
+        sudo unzip -qo instantclient-sdk-linux.x64-21.15.0.0.0dbru.zip -d /opt/oracle
+        echo "/opt/oracle/instantclient_21_15" >> $GITHUB_PATH
+    - name: Install JDBC Driver
+      run: |
+        wget -q https://download.oracle.com/otn-pub/otn_software/jdbc/23261/ojdbc11.jar -O ./lib/ojdbc11.jar
+    - name: Configure ORA_TZFILE to match Oracle 11g server
+      run: |
+        # Oracle 11g XE uses timezone file v14; Instant Client 21.15 embeds
+        # v35. This mismatch causes ORA-01805 when fetching DATE/TIMESTAMP
+        # values. Copy the v14 files from the 11g container and point the
+        # Instant Client at them via ORA_TZFILE.
+        ORACLE_CONTAINER="${{ job.services.oracle.id }}"
+        sudo mkdir -p "$ORACLE_HOME/oracore/zoneinfo"
+        docker cp "$ORACLE_CONTAINER":/u01/app/oracle/product/11.2.0/xe/oracore/zoneinfo/timezlrg_14.dat /tmp/timezlrg_14.dat
+        docker cp "$ORACLE_CONTAINER":/u01/app/oracle/product/11.2.0/xe/oracore/zoneinfo/timezone_14.dat /tmp/timezone_14.dat
+        sudo mv /tmp/timezlrg_14.dat "$ORACLE_HOME/oracore/zoneinfo/"
+        sudo mv /tmp/timezone_14.dat "$ORACLE_HOME/oracore/zoneinfo/"
+        echo "ORA_TZFILE=timezlrg_14.dat" >> $GITHUB_ENV
+    - name: Create database user
+      run: |
+        ./ci/setup_accounts.sh
+    - name: Bundle install
+      run: |
+        bundle install --jobs 4 --retry 3
+    - name: Run RSpec
+      run: |
+        RUBYOPT=-w bundle exec rspec