Testsuite: Rename 4500-Domain-Keys-Identified-Mail for consistency

diff --git a/test/scripts/4500-Domain-Keys-Identified-Mail/4500 b/test/scripts/4500-DKIM/4500
similarity index 100%
rename from test/scripts/4500-Domain-Keys-Identified-Mail/4500
rename to test/scripts/4500-DKIM/4500

diff --git a/test/scripts/4500-Domain-Keys-Identified-Mail/4501 b/test/scripts/4500-DKIM/4501
similarity index 100%
rename from test/scripts/4500-Domain-Keys-Identified-Mail/4501
rename to test/scripts/4500-DKIM/4501

diff --git a/test/scripts/4500-Domain-Keys-Identified-Mail/4502 b/test/scripts/4500-DKIM/4502
similarity index 100%
rename from test/scripts/4500-Domain-Keys-Identified-Mail/4502
rename to test/scripts/4500-DKIM/4502

diff --git a/test/scripts/4500-Domain-Keys-Identified-Mail/4503 b/test/scripts/4500-DKIM/4503
similarity index 100%
rename from test/scripts/4500-Domain-Keys-Identified-Mail/4503
rename to test/scripts/4500-DKIM/4503

diff --git a/test/scripts/4500-Domain-Keys-Identified-Mail/4509 b/test/scripts/4500-DKIM/4509
similarity index 100%
rename from test/scripts/4500-Domain-Keys-Identified-Mail/4509
rename to test/scripts/4500-DKIM/4509

diff --git a/test/scripts/4500-Domain-Keys-Identified-Mail/REQUIRES b/test/scripts/4500-DKIM/REQUIRES
similarity index 100%
rename from test/scripts/4500-Domain-Keys-Identified-Mail/REQUIRES
rename to test/scripts/4500-DKIM/REQUIRES