[drake_bazel_external_legacy] Pin to Drake v1.44 (#427)

Note the imminent removal of this example.
Disable CI (no longer makes sense to test Drake's master branch).

Also fix string literal warning in file_sync_test.

Author: jwnimmer-tri

Jenkinsfile

@@ -26,7 +26,7 @@ if (env.BRANCH_NAME == 'main') {
 
 properties(props)
 
-def examples = ['drake_bazel_external', 'drake_bazel_external_legacy', 'drake_cmake_external']
+def examples = ['drake_bazel_external', 'drake_cmake_external']
 def jobs = [:]
 
 for (example in examples) {

drake_bazel_external_legacy/.github/ci_build_test

@@ -3,9 +3,10 @@
 This pulls in Drake and builds it from source via Bazel's WORKSPACE mechanism,
 which is deprecated as of Bazel 8 and will be removed in Bazel 9. Therefore,
 we do not recommend using this example for new projects; instead, refer to
-the `drake_bazel_external` example. The legacy example primarily serves
-as a regression test for the deprecated behavior, and therefore uses Drake's
-minimum supported Bazel version.
+the `drake_bazel_external` example.
+
+The WORKSPACE mechanism is only supported for Drake v1.44.0 and earlier. This
+example will be deleted after the next version of Drake (v1.45.0) is released.
 
 For an introduction to Bazel, refer to
 [Getting Started with Bazel](https://bazel.build/start).

drake_bazel_external_legacy/.github/setup

@@ -2,8 +2,8 @@
 
 workspace(name = "drake_external_examples")
 
-DRAKE_COMMIT = "master"
-DRAKE_CHECKSUM = ""
+DRAKE_COMMIT = "v1.44.0"
+DRAKE_CHECKSUM = "6df6dc50f2df53ebb526b01995e1f604ee5f8a546dcda23428449bcfd1fb3e6b"
 
 # Or choose a specific revision of Drake to use.
 # DRAKE_COMMIT = "be4f658487f739ba04ec079de46f9459b719636d"

drake_bazel_external_legacy/.github/ubuntu_setup

@@ -4,7 +4,7 @@
 
 set -euxo pipefail
 
-drake_commit_hash='master'
+drake_commit_hash='v1.44.0'
 
 while [ "${1:-}" != "" ]; do
   case "$1" in

drake_bazel_external_legacy/README.md

@@ -60,8 +60,6 @@
         ".bazelignore",
         ".bazelproject",
         ".clang-format",
-        ".github/setup",
-        ".github/ubuntu_setup",
         "BUILD.bazel",
         "CPPLINT.cfg",
         "LICENSE",
@@ -77,7 +75,6 @@
         "apps/simple_adder_test.cc",
         "apps/simple_continuous_time_system.cc",
         "apps/simple_logging_example.py",
-        "setup/install_prereqs",
     ]
 ]) + tuple([
     (
@@ -221,7 +218,7 @@ def check_sep(paths, sep):
 
     root_dispatch = content[root_ci_path].split(seps["dispatch"])[1].split(seps["conc"])[0]
     subdir_dispatch = content[subdir_ci_path].split(seps["dispatch"])[1].split(seps["conc"])[0]
-    subdir_dispatch = re.sub("[^\S\r\n]{6}", "", subdir_dispatch) # remove leading indendation
+    subdir_dispatch = re.sub(r"[^\S\r\n]{6}", "", subdir_dispatch)  # Remove leading indentation.
 
     # Check that the root workflow defines no extra options
     # beyond what is configured here.