trace: update gen.bash for Go 1.24

As of CL 593975, the testdata debugging tools are part of cmd/trace.

Change-Id: I5811462055869cefb80a8586f16031e0257d8ee8
Reviewed-on: https://go-review.googlesource.com/c/exp/+/669255
Reviewed-by: Carlos Amedee <[email protected]>
Auto-Submit: Rhys Hiltner <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>
Reviewed-by: Cherry Mui <[email protected]>

Author: rhysh

trace/gen.bash

@@ -70,9 +70,6 @@ mv $DST/event $DST/internal/event
 mv $DST/version $DST/internal/version
 mv $DST/testtrace $DST/internal/testtrace
 
-# Move the debug commands out of testdata.
-mv $DST/testdata/cmd $DST/cmd
-
 # Fix up import paths.
 find $DST -name '*.go' | xargs -- sed -i'.tmp' -e 's internal/trace golang.org/x/exp/trace '
 find $DST -name '*.go' | xargs -- sed -i'.tmp' -e 's golang.org/x/exp/trace/raw golang.org/x/exp/trace/internal/raw '
@@ -87,7 +84,7 @@ find $DST -name '*.go' | xargs -- sed -i'.tmp' -e '/LICENSE file./a \
 \
 // Code generated by "gen.bash" from internal/trace; DO NOT EDIT.\
 \
-//go:build go1.21'
+//go:build go1.23'
 
 # Format the files.
 find $DST -name '*.go' | xargs -- gofmt -w -s