test: Add copyright-check workflow

Also Use -v flag in CI

.github/workflows/check-copyright.yml

@@ -0,0 +1,18 @@
+name: Copyright years
+on: [pull_request, push]
+permissions:
+  contents: read
+
+jobs:
+  copyright-notice:
+    runs-on: ubuntu-latest
+    name: Test changed-files
+    steps:
+    - name: Get changed files
+      id: changed-files
+      uses: tj-actions/changed-files@v44
+    - uses: actions/checkout@v4
+    - name: Check changed files
+      env:
+        ALL_CHANGED_FILES: ${{ steps.changed-files.outputs.all_changed_files }}
+      run: perl ./ietf/check-copyright -lv -f ${ALL_CHANGED_FILES};

ietf/check-copyright

@@ -6,9 +6,6 @@ use warnings;
 use POSIX qw/strftime/;
 use Getopt::Std;
 
-# Getopt settings.
-our($opt_f, $opt_h, $opt_c, $opt_l, $opt_m);
-
 # Number of errors found; exit status
 my $ERRORS = 0;
 
@@ -18,14 +15,18 @@ my $some_year  = "[12][0-9][0-9][0-9]";
 my $year_range = "(${some_year})(-${some_year})?";
 my $copyright  = "Copyright The IETF Trust *${year_range}";
 
+# Getopt settings.
+our($opt_h, $opt_f, $opt_v, $opt_c, $opt_l, $opt_m);
+
 sub
 usage()
 {
     my $retcode = pop();
 
     print STDERR "Options:\n";
-    print STDERR "    -f   Read filenames from argv\n";
     print STDERR "    -h   This help message\n";
+    print STDERR "    -f   Read filenames from argv\n";
+    print STDERR "    -v   List files as processed\n";
     print STDERR "    -c   Modify files that should be changed\n";
     print STDERR "         (Does not do a git commit)\n";
     print STDERR "    -l   List files that need to be changed\n";
@@ -66,6 +67,8 @@ process()
     my $changed = 0;
     my $SAVE;
 
+    print "# Processing $NAME\n" if defined $opt_v;
+
     # ignore ZIP files
     return if $NAME =~ /\.zip/;