tests: use %TESTNUMBER instead of fixed number

This makes the tests easier to copy and relocate to other test numbers
without having to update content.

Closes #6738

tests/data/test2002

@@ -58,9 +58,9 @@ tftp
 HTTP GET followed by FTP RETR followed by FILE followed by TFTP RRQ
  </name>
 <command option="no-include">
-http://%HOSTIP:%HTTPPORT/20020001 ftp://%HOSTIP:%FTPPORT/20020002 file://localhost%FILE_PWD/log/test2002.txt tftp://%HOSTIP:%TFTPPORT//20020003
+http://%HOSTIP:%HTTPPORT/%TESTNUMBER0001 ftp://%HOSTIP:%FTPPORT/%TESTNUMBER0002 file://localhost%FILE_PWD/log/test%TESTNUMBER.txt tftp://%HOSTIP:%TFTPPORT//%TESTNUMBER0003
 </command>
-<file name="log/test2002.txt">
+<file name="log/test%TESTNUMBER.txt">
 foo
    bar
 bar
@@ -73,7 +73,7 @@ moo
 # Verify data after the test has been "shot"
 <verify>
 <protocol>
-GET /20020001 HTTP/1.1
+GET /%TESTNUMBER0001 HTTP/1.1
 Host: %HOSTIP:%HTTPPORT
 User-Agent: curl/%VERSION
 Accept: */*
@@ -83,14 +83,14 @@ PASS ftp@example.com
 PWD
 EPSV
 TYPE I
-SIZE 20020002
-RETR 20020002
+SIZE %TESTNUMBER0002
+RETR %TESTNUMBER0002
 opcode: 1
 mode: octet
 tsize: 0
 blksize: 512
 timeout: 6
-filename: /20020003
+filename: /%TESTNUMBER0003
 QUIT
 </protocol>
 <stdout>