[mgmt][pipeline] Remove global configuration "multiapi"

[msyyc]

Only small amount of mgmt packages are multiapi-packages, so "multiapi" shall not be global configuration in swagger pipeline.
test link: openapi-env-test/azure-rest-api-specs#3141

steps:
(1) update template files:
Azure/azure-rest-api-specs#19157

(2) update existing multiapi configuration
https://github.com/msyyc/file-storage/blob/release-sdk-status/release_sdk_status.csv

(3) remove global "multiapi" configuration
#24542