Add date as a parameter for determineSupportedRange

pr-checks/update-ghes-versions.ts

@@ -125,6 +125,7 @@ export function addWeeks(date: Date, weeks: number): Date {
 
 /** Determines the current range of GHES versions we should support. */
 export function determineSupportedRange(
+  today: Date,
   apiCompatibilityData: ApiCompatibility,
   releases: EnterpriseReleases,
 ): ApiCompatibility {
@@ -145,8 +146,6 @@ export function determineSupportedRange(
     );
   }
 
-  const today = new Date();
-
   // NOTE: We deliberately omit including any data from `releases` in the error messages below.
 
   for (const [releaseVersionString, releaseData] of Object.entries(releases)) {
@@ -211,6 +210,7 @@ function main() {
 
   // Determine the supported range.
   const newCompatibilityData: ApiCompatibility = determineSupportedRange(
+    new Date(),
     apiCompatibilityData,
     releases,
   );