Bump build to 2.19.7.4.

// FREEBIE

Author: charlesmchen

Signal/Signal-Info.plist

@@ -55,7 +55,7 @@
 		</dict>
 	</array>
 	<key>CFBundleVersion</key>
-	<string>2.19.7.3</string>
+	<string>2.19.7.4</string>
 	<key>ITSAppUsesNonExemptEncryption</key>
 	<false/>
 	<key>LOGS_EMAIL</key>