Fix the issue of indexPrefixMap being unordered, which causes the IndexStoreDB path to be unpredictable.#2177

ahoppen merged 2 commits intoswiftlang:mainswiftlang/sourcekit-lsp:mainfrom

Kila2:feature/sort_prefixmapperKila2/sourcekit-lsp:feature/sort_prefixmapperCopy head branch name to clipboard