Ignore unit-tests ci when the pull requeat only change doc (#7955)

Signed-off-by: Nxiaolong.ran <rxl@apache.org>

.github/workflows/ci-unit.yaml

@@ -42,22 +42,34 @@ jobs:
           fetch-depth: 0
           ref: ${{ github.event.pull_request.head.sha }}
 
+      - name: Check if this pull request only changes documentation
+        id:   docs
+        uses: apache/pulsar-test-infra/diff-only@master
+        with:
+          args: site2 deployment .asf.yaml .ci ct.yaml
+
       - name: build and run unit tests exclude pulsar-broker and pulsar-proxy
+        if: steps.docs.outputs.changed_only == 'no'
         run: ./build/retry.sh mvn -B -ntp install -PbrokerSkipTest -Dexclude="org/apache/pulsar/proxy/**/*.java,**/KafkaProducerSimpleConsumerTest.java,**/ManagedLedgerTest.java,**/TestPulsarKeyValueSchemaHandler.java,**/PrimitiveSchemaTest.java,**/BlobStoreManagedLedgerOffloaderTest.java"
 
       - name: run flaky test "**/ManagedLedgerTest.java"
+        if: steps.docs.outputs.changed_only == 'no'
         run: ./build/retry.sh mvn -B -ntp test -pl managed-ledger -Dinclude="**/ManagedLedgerTest.java" -DtestForkCount=1 -DtestReuseFork=true
 
       - name: run flaky test "**/KafkaProducerSimpleConsumerTest.java"
+        if: steps.docs.outputs.changed_only == 'no'
         run: ./build/retry.sh mvn -B -ntp test -pl pulsar-client-kafka-compat/pulsar-client-kafka_0_8 -Dinclude="**/KafkaProducerSimpleConsumerTest.java" -DtestForkCount=1 -DtestReuseFork=true
 
       - name: run flaky test "**/TestPulsarKeyValueSchemaHandler.java"
+        if: steps.docs.outputs.changed_only == 'no'
         run: ./build/retry.sh mvn -B -ntp test -pl pulsar-sql/presto-pulsar-plugin -Dinclude="**/TestPulsarKeyValueSchemaHandler.java" -DtestForkCount=1 -DtestReuseFork=true
 
       - name: run flaky test "**/PrimitiveSchemaTest.java"
+        if: steps.docs.outputs.changed_only == 'no'
         run: ./build/retry.sh mvn -B -ntp test -pl pulsar-client -Dinclude="**/PrimitiveSchemaTest.java" -DtestForkCount=1 -DtestReuseFork=true
 
       - name: run flaky test "**/BlobStoreManagedLedgerOffloaderTest.java"
+        if: steps.docs.outputs.changed_only == 'no'
         run: ./build/retry.sh mvn -B -ntp test -pl tiered-storage/jcloud -Dinclude="**/BlobStoreManagedLedgerOffloaderTest.java" -DtestForkCount=1 -DtestReuseFork=true
 
       - name: package surefire artifacts