[release-1.29] change default of statsCompression to true

[istio-testing]

Manual cherrypick required.

#3641 failed to apply on top of branch "release-1.29":

Applying: change default of statsCompression to true
Using index info to reconstruct a base tree...
M	mesh/v1alpha1/istio.mesh.v1alpha1.pb.html
M	mesh/v1alpha1/proxy.pb.go
M	mesh/v1alpha1/proxy.proto
Falling back to patching base and 3-way merge...
Auto-merging mesh/v1alpha1/proxy.proto
CONFLICT (content): Merge conflict in mesh/v1alpha1/proxy.proto
Auto-merging mesh/v1alpha1/proxy.pb.go
CONFLICT (content): Merge conflict in mesh/v1alpha1/proxy.pb.go
Auto-merging mesh/v1alpha1/istio.mesh.v1alpha1.pb.html
CONFLICT (content): Merge conflict in mesh/v1alpha1/istio.mesh.v1alpha1.pb.html
error: Failed to merge in the changes.
hint: Use 'git am --show-current-patch=diff' to see the failed patch
hint: When you have resolved this problem, run "git am --continue".
hint: If you prefer to skip this patch, run "git am --skip" instead.
hint: To restore the original branch and stop patching, run "git am --abort".
hint: Disable this message with "git config set advice.mergeConflict false"
Patch failed at 0001 change default of statsCompression to true