patch 9.1.0593: filetype: Asymptote files are not recognized

Problem:  filetype: Asymptote files are not recognized
Solution: detect '*.asy' files as asy filetype, include
          ftplugin and syntax plugin (AvidSeeker).

Reference: https://asymptote.sourceforge.io/

closes: #15252

Signed-off-by: AvidSeeker <avidseeker7@protonmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/test_filetype.vim b/src/testdir/test_filetype.vim
index 9e66a7c..c3c0139 100644
--- a/src/testdir/test_filetype.vim
+++ b/src/testdir/test_filetype.vim
@@ -107,6 +107,7 @@
     asn: ['file.asn', 'file.asn1'],
     asterisk: ['asterisk/file.conf', 'asterisk/file.conf-file', 'some-asterisk/file.conf', 'some-asterisk/file.conf-file'],
     astro: ['file.astro'],
+    asy: ['file.asy'],
     atlas: ['file.atl', 'file.as'],
     authzed: ['schema.zed'],
     autohotkey: ['file.ahk'],
diff --git a/src/version.c b/src/version.c
index c6b6248..49aeb92 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    593,
+/**/
     592,
 /**/
     591,