Rename Soy map to legacy_object_map (first step of migration)

See []for more information.

Created with the tools in []
Tested:
    TAP --sample for global presubmit queue
    []

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184727400

java/google/registry/tools/soy/DomainAllocate.soy

@@ -21,7 +21,7 @@
 {@param name: string}
 {@param period: int}
 {@param registrant: string}
-{@param contacts: map<string, string>}
+{@param contacts: legacy_object_map<string, string>}
 {@param authInfo: string}
 {@param applicationRoid: string}
 {@param applicationTime: string}