aconfig: remove the 'debug' dump format

The --format=debug dump output format is largely superseded by the
textproto format now that aconfig doesn't use hand-written wrappers
around the auto-generated proto struct anymore. Remove the format to
reduce the risk of code rot.

Bug: 283910447
Test: atest aconfig.test
Change-Id: I6700fc4eafd3fa3a63952109c0105d34c7ffd98b
diff --git a/tools/aconfig/src/commands.rs b/tools/aconfig/src/commands.rs
index bf45921..2e2aa0f 100644
--- a/tools/aconfig/src/commands.rs
+++ b/tools/aconfig/src/commands.rs
@@ -213,7 +213,6 @@
 #[derive(Copy, Clone, Debug, PartialEq, Eq, ValueEnum)]
 pub enum DumpFormat {
     Text,
-    Debug,
     Protobuf,
     Textproto,
 }
@@ -238,12 +237,6 @@
                 output.extend_from_slice(line.as_bytes());
             }
         }
-        DumpFormat::Debug => {
-            for parsed_flag in parsed_flags.parsed_flag.into_iter() {
-                let line = format!("{:#?}\n", parsed_flag);
-                output.extend_from_slice(line.as_bytes());
-            }
-        }
         DumpFormat::Protobuf => {
             parsed_flags.write_to_vec(&mut output)?;
         }