Clean up CI workflows and remove placeholder example files

- Remove spark-4-support branch triggers from all workflows
- Standardize Java version comments to 'Java 11+ (using Java 17)'
- Remove empty placeholder files:
  - SimpleBatchExample.scala
  - StreamingRateExample.scala
  - DEBUGGING.md
  - run-example.sh
- Keep actual working examples in spark-4.0/examples/src/main/scala/examples/

Author: ShimonSte

.github/workflows/check-license.yml

@@ -18,12 +18,10 @@ on:
     branches:
       - "branch-*"
       - "main"
-      - "spark-4-support"
   pull_request:
     branches:
       - "branch-*"
       - "main"
-      - "spark-4-support"
 
 jobs:
   check-license:

.github/workflows/cloud.yml

@@ -19,12 +19,10 @@ on:
     branches:
       - "branch-*"
       - "main"
-      - "spark-4-support"
   pull_request:
     branches:
       - "branch-*"
       - "main"
-      - "spark-4-support"
   workflow_dispatch:
 
 jobs:
@@ -40,15 +38,15 @@ jobs:
         scala: [ '2.12', '2.13' ]
         java: [ 8 ]
         include:
-          # Spark 4.0 requires Java 17
+          # Spark 4.0 requires Java 11+ (using Java 17)
           - spark: '4.0'
             scala: '2.13'
             java: 17
         exclude:
           # Spark 4.0 only supports Scala 2.13
           - spark: '4.0'
             scala: '2.12'
-          # Spark 4.0 requires Java 11+ (will use Java 17 from include)
+          # Spark 4.0 requires Java 11+
           - spark: '4.0'
             java: 8
     env:

.github/workflows/style.yml

@@ -19,12 +19,10 @@ on:
     branches:
       - "branch-*"
       - "main"
-      - "spark-4-support"
   pull_request:
     branches:
       - "branch-*"
       - "main"
-      - "spark-4-support"
 
 jobs:
   check-style:

.github/workflows/tpcds.yml

@@ -19,12 +19,10 @@ on:
     branches:
       - "branch-*"
       - "main"
-      - "spark-4-support"
   pull_request:
     branches:
       - "branch-*"
       - "main"
-      - "spark-4-support"
 
 jobs:
   run-tpcds-sf1:
@@ -36,15 +34,15 @@ jobs:
         scala: [ '2.12', '2.13' ]
         java: [ 8 ]
         include:
-          # Spark 4.0 requires Java 17
+          # Spark 4.0 requires Java 11+ (using Java 17)
           - spark: '4.0'
             scala: '2.13'
             java: 17
         exclude:
           # Spark 4.0 only supports Scala 2.13
           - spark: '4.0'
             scala: '2.12'
-          # Spark 4.0 requires Java 11+ (will use Java 17 from include)
+          # Spark 4.0 requires Java 11+
           - spark: '4.0'
             java: 8
     steps: