Fix spelling error and wrap output at 80 columns.

Bug: 362787698
Change-Id: I5d31783dd8f659ba6e5e37c2f3961971874e851e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/5851653
Reviewed-by: Josip Sokcevic <sokcevic@chromium.org>
Commit-Queue: Josip Sokcevic <sokcevic@chromium.org>
Commit-Queue: Peter Kasting <pkasting@chromium.org>
Auto-Submit: Peter Kasting <pkasting@chromium.org>

gclient_scm.py

@@ -690,10 +690,10 @@ class GitWrapper(SCMWrapper):
                         "This may cause unexpected behavior with submodules; "
                         "see //docs/git_submodules.md\n"
                         "Consider setting the config:\n"
-                        "\tgit config diff.ignoreSubmodule dirty\n"
+                        "\tgit config diff.ignoreSubmodules dirty\n"
                         "or disable this warning by setting the "
-                        "GCLIENT_SUPPRESS_SUBMODULE_WARNING environment "
-                        "variable to 1.")
+                        "GCLIENT_SUPPRESS_SUBMODULE_WARNING\n"
+                        "environment variable to 1.")
                     if os.environ.get(
                             'GCLIENT_SUPPRESS_SUBMODULE_WARNING') != '1':
                         gclient_utils.AddWarning(warning_message)