ICU-23231 ICU 78.3 on bottom of the 78 page

Author: markusicu

docs/download/78.md

@@ -235,13 +235,17 @@ ICU4J should work on Android API level 21 and later but may require “[library
 ### GitHub
 Source and binary downloads are available on the git/GitHub tag page:
 
+* 78.3: <https://github.com/unicode-org/icu/releases/tag/release-78.3>
 * 78.2: <https://github.com/unicode-org/icu/releases/tag/release-78.2>
 * 78.1: <https://github.com/unicode-org/icu/releases/tag/release-78.1>
 
 See the [Source Code Setup](../devsetup/source/) page for how to download the ICU file tree directly from GitHub.
 
 ICU locale data was generated from CLDR data equivalent to:
 
+* 78.3:
+    * <https://github.com/unicode-org/cldr/releases/tag/release-48-2>
+    * <https://github.com/unicode-org/cldr-staging/releases/tag/release-48-2>
 * 78.2:
     * <https://github.com/unicode-org/cldr/releases/tag/release-48-1-final1>
     * <https://github.com/unicode-org/cldr-staging/releases/tag/release-48-1-final1>
@@ -250,5 +254,6 @@ ICU locale data was generated from CLDR data equivalent to:
     * <https://github.com/unicode-org/cldr-staging/releases/tag/release-48>
 
 ### Maven
+* https://mvnrepository.com/artifact/com.ibm.icu/icu4j/78.3
 * https://mvnrepository.com/artifact/com.ibm.icu/icu4j/78.2
 * https://mvnrepository.com/artifact/com.ibm.icu/icu4j-charset/78.2