feat(contrib/fetchroots): track git revisions

Change-Id: I3af0a4486a8685191adc28210162661fae6cfc3c
Reviewed-on: https://cl.snix.dev/c/snix/+/30290
Reviewed-by: Florian Klink <flokli@flokli.de>
Tested-by: besadii

contrib/fetchroots/Cargo.lock

@@ -917,9 +917,9 @@ dependencies = [
 
 [[package]]
 name = "data-encoding"
-version = "2.6.0"
+version = "2.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e8566979429cf69b49a5c740c60791108e86440e8be149bbea4fe54d2c32d6e2"
+checksum = "575f75dfd25738df5b91b8e43e14d44bda14637a58fae779fd2b064f8bf3e010"
 
 [[package]]
 name = "der"
@@ -1099,6 +1099,7 @@ dependencies = [
  "bytes-utils",
  "bzip2",
  "chrono",
+ "data-encoding",
  "futures",
  "indicatif",
  "nix-compat",