[FEATURE] Add specs for `performance_analyzer` namespace

[nhtruong]

Part of Adding missing API specs issue

• /_plugins/_performanceanalyzer/_agent/{redirectEndpoint}: ["GET"]
• /_plugins/_performanceanalyzer/batch/cluster/config: ["GET","POST"]
• /_plugins/_performanceanalyzer/batch/config: ["GET","POST"]
• /_plugins/_performanceanalyzer/cluster/config: ["GET","POST"]
• /_plugins/_performanceanalyzer/config: ["GET","POST"]
• /_plugins/_performanceanalyzer/logging/cluster/config: ["GET","POST"]
• /_plugins/_performanceanalyzer/logging/config: ["GET","POST"]
• /_plugins/_performanceanalyzer/override/cluster/config: ["GET","POST"]
• /_plugins/_performanceanalyzer/rca/cluster/config: ["GET","POST"]
• /_plugins/_performanceanalyzer/rca/config: ["GET","POST"]
• /_plugins/_performanceanalyzer/threadContentionMonitoring/cluster/config: ["GET","POST"]
• /_plugins/_performanceanalyzer/threadContentionMonitoring/config: ["GET","POST"]

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(Should be handled by superseded_operations)

• /_opendistro/_performanceanalyzer/_agent/{redirectEndpoint}: ["GET"]
• /_opendistro/_performanceanalyzer/batch/cluster/config: ["GET","POST"]
• /_opendistro/_performanceanalyzer/batch/config: ["GET","POST"]
• /_opendistro/_performanceanalyzer/cluster/config: ["GET","POST"]
• /_opendistro/_performanceanalyzer/config: ["GET","POST"]
• /_opendistro/_performanceanalyzer/logging/cluster/config: ["GET","POST"]
• /_opendistro/_performanceanalyzer/logging/config: ["GET","POST"]
• /_opendistro/_performanceanalyzer/override/cluster/config: ["GET","POST"]
• /_opendistro/_performanceanalyzer/rca/cluster/config: ["GET","POST"]
• /_opendistro/_performanceanalyzer/rca/config: ["GET","POST"]