Use max-parallel: 20 as asked by Apache Infra

Author: garydgregory

.github/workflows/codeql-analysis.yml

@@ -37,6 +37,7 @@ jobs:
       security-events: write
 
     strategy:
+      max-parallel: 20
       fail-fast: false
       matrix:
         language: [ 'java' ]

.github/workflows/coverage.yml

@@ -36,6 +36,7 @@ jobs:
 
     runs-on: ubuntu-latest
     strategy:
+      max-parallel: 20
       matrix:
         java: [ 11 ] # Use 11 rather than 8, as 8 fails currently
 

.github/workflows/maven.yml

@@ -36,6 +36,7 @@ jobs:
 
     runs-on: ${{ matrix.os }}
     strategy:
+      max-parallel: 20
       fail-fast: false # Run all the versions, but show overall status as failed if one fails
       matrix:
         os: [ ubuntu-latest, macos-13, windows-latest ]

.github/workflows/maven_legacy.yml

@@ -32,6 +32,7 @@ jobs:
 
     runs-on: ${{ matrix.os }}
     strategy:
+      max-parallel: 20
       fail-fast: false # Run all the versions, but show overall status as failed if one fails
       matrix:
         os: [ ubuntu-latest, macos-13, windows-latest ]