cmd/tailscale/main: remove tracked aar lib (#183)

Updates tailscale/tailscale#10748

The built aar should not be checked into android_legacy.

Signed-off-by: Jonathan Nobels <jonathan@tailscale.com>

.gitignore

@@ -6,6 +6,7 @@ build
 
 # The destination for the Go Android archive.
 android/libs
+android_legacy/libs
 
 # Android Studio files
 android_legacy/.idea
@@ -30,4 +31,4 @@ tailscale.jks
 *.hprof
 
 #IDE
-.vscode
+.vscode