Update branding to 8.0.15 (#13088)

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Author: LeafShi1

eng/Versions.props

@@ -3,7 +3,7 @@
   <PropertyGroup>
     <MajorVersion>8</MajorVersion>
     <MinorVersion>0</MinorVersion>
-    <PatchVersion>14</PatchVersion>
+    <PatchVersion>15</PatchVersion>
     <!-- version in our package name #.#.#-below.#####.## -->
     <PreReleaseVersionLabel>servicing</PreReleaseVersionLabel>
     <PreReleaseVersionIteration>