fix: honor server-directed FDv1 Fallback Directive in initializer phase#423

keelerm84 wants to merge 5 commits intomainlaunchdarkly/python-server-sdk:mainfrom

mk/sdk-2290/fdv1-fallbacklaunchdarkly/python-server-sdk:mk/sdk-2290/fdv1-fallbackCopy head branch name to clipboard