Delete old BBR and pacer implementations in the recovery/congestion directory. (#2297)

We recommend use of:
* the cubic implementation, without pacing
* the bbr2 implementation from the gcongestion directory, with pacing. Note that pacing only works correctly on Linux and if TxTime is available (qdisc fq kernel module enabled).

Author: antoniovicente

quiche/Cargo.toml

@@ -70,7 +70,6 @@ cdylib-link-lines = { version = "0.1", optional = true }
 
 [dependencies]
 boring = { workspace = true, optional = true }
-debug_panic = { version = "0.2.1" }
 either = { version = "1.8", default-features = false }
 foreign-types-shared = { version = "0.3.0", optional = true }
 intrusive-collections = "0.9.5"

quiche/src/minmax.rs

@@ -118,6 +118,7 @@ impl<T: PartialOrd + Copy> Minmax<T> {
     }
 
     /// Updates the max estimate based on the given measurement, and returns it.
+    #[cfg(test)]
     pub fn running_max(&mut self, win: Duration, time: Instant, meas: T) -> T {
         let val = MinmaxSample { time, value: meas };