[3.7] Bump Azure Pipelines to ubuntu-20.04 (GH-101089). (GH-101226)

Co-authored-by: Hugo van Kemenade <[email protected]>

Author: hugovk

.azure-pipelines/ci.yml

@@ -12,7 +12,7 @@ jobs:
   displayName: Pre-build checks
 
   pool:
-    vmImage: ubuntu-16.04
+    vmImage: ubuntu-20.04
 
   steps:
   - template: ./prebuild-checks.yml
@@ -24,7 +24,7 @@ jobs:
   condition: and(succeeded(), eq(dependencies.Prebuild.outputs['docs.run'], 'true'))
 
   pool:
-    vmImage: ubuntu-16.04
+    vmImage: ubuntu-20.04
 
   steps:
   - template: ./docs-steps.yml
@@ -56,7 +56,7 @@ jobs:
   condition: and(succeeded(), eq(dependencies.Prebuild.outputs['tests.run'], 'true'))
 
   pool:
-    vmImage: ubuntu-16.04
+    vmImage: ubuntu-20.04
 
   variables:
     testRunTitle: '$(build.sourceBranchName)-linux'
@@ -82,7 +82,7 @@ jobs:
     )
 
   pool:
-    vmImage: ubuntu-16.04
+    vmImage: ubuntu-20.04
 
   container: manylinux1
 
@@ -113,7 +113,7 @@ jobs:
     )
 
   pool:
-    vmImage: ubuntu-16.04
+    vmImage: ubuntu-20.04
 
   variables:
     testRunTitle: '$(Build.SourceBranchName)-linux-coverage'

.azure-pipelines/pr.yml

@@ -12,7 +12,7 @@ jobs:
   displayName: Pre-build checks
 
   pool:
-    vmImage: ubuntu-16.04
+    vmImage: ubuntu-20.04
 
   steps:
   - template: ./prebuild-checks.yml
@@ -24,7 +24,7 @@ jobs:
   condition: and(succeeded(), eq(dependencies.Prebuild.outputs['docs.run'], 'true'))
 
   pool:
-    vmImage: ubuntu-16.04
+    vmImage: ubuntu-20.04
 
   steps:
   - template: ./docs-steps.yml
@@ -56,7 +56,7 @@ jobs:
   condition: and(succeeded(), eq(dependencies.Prebuild.outputs['tests.run'], 'true'))
 
   pool:
-    vmImage: ubuntu-16.04
+    vmImage: ubuntu-20.04
 
   variables:
     testRunTitle: '$(system.pullRequest.TargetBranch)-linux'
@@ -82,7 +82,7 @@ jobs:
     )
 
   pool:
-    vmImage: ubuntu-16.04
+    vmImage: ubuntu-20.04
 
   container: manylinux1
 
@@ -113,7 +113,7 @@ jobs:
     )
 
   pool:
-    vmImage: ubuntu-16.04
+    vmImage: ubuntu-20.04
 
   variables:
     testRunTitle: '$(Build.SourceBranchName)-linux-coverage'