Update Dagger yml and README with latest version number.

RELNOTES=N/A
PiperOrigin-RevId: 709094695

Author: bcorso

README.md

@@ -38,8 +38,8 @@ release.
 
 load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
 
-DAGGER_TAG = "2.53.1"
-DAGGER_SHA = "b82f1133b623892617f9e64fd14ba9203647e470a32048ba8aa26075bbb8a9e5"
+DAGGER_TAG = "2.54"
+DAGGER_SHA = "f7fd174ef9bb0fe7b23b50c500f78e19b64ce762169fa7a97c7171658d82834c"
 http_archive(
     name = "dagger",
     strip_prefix = "dagger-dagger-%s" % DAGGER_TAG,