test: fix partitions test to use correct partition type

[tomasmatus]

Fixes: #22922

Libblockdev now validates the partition type and throws an error if the type does not exist. storaged-project/libblockdev#1168

[tomasmatus]

FTR these are DOS partition types from fdisk, as you can see C8 is not there.

00 Empty            27 Hidden NTFS Win  82 Linux swap / So  c1 DRDOS/sec (FAT-
01 FAT12            39 Plan 9           83 Linux            c4 DRDOS/sec (FAT-
02 XENIX root       3c PartitionMagic   84 OS/2 hidden or   c6 DRDOS/sec (FAT-
03 XENIX usr        40 Venix 80286      85 Linux extended   c7 Syrinx         
04 FAT16 <32M       41 PPC PReP Boot    86 NTFS volume set  da Non-FS data    
05 Extended         42 SFS              87 NTFS volume set  db CP/M / CTOS / .
06 FAT16            4d QNX4.x           88 Linux plaintext  de Dell Utility   
07 HPFS/NTFS/exFAT  4e QNX4.x 2nd part  8e Linux LVM        df BootIt         
08 AIX              4f QNX4.x 3rd part  93 Amoeba           e1 DOS access     
09 AIX bootable     50 OnTrack DM       94 Amoeba BBT       e3 DOS R/O        
0a OS/2 Boot Manag  51 OnTrack DM6 Aux  9f BSD/OS           e4 SpeedStor      
0b W95 FAT32        52 CP/M             a0 IBM Thinkpad hi  ea Linux extended 
0c W95 FAT32 (LBA)  53 OnTrack DM6 Aux  a5 FreeBSD          eb BeOS fs        
0e W95 FAT16 (LBA)  54 OnTrackDM6       a6 OpenBSD          ee GPT            
0f W95 Ext'd (LBA)  55 EZ-Drive         a7 NeXTSTEP         ef EFI (FAT-12/16/
10 OPUS             56 Golden Bow       a8 Darwin UFS       f0 Linux/PA-RISC b
11 Hidden FAT12     5c Priam Edisk      a9 NetBSD           f1 SpeedStor      
12 Compaq diagnost  61 SpeedStor        ab Darwin boot      f4 SpeedStor      
14 Hidden FAT16 <3  63 GNU HURD or Sys  af HFS / HFS+       f2 DOS secondary  
16 Hidden FAT16     64 Novell Netware   b7 BSDI fs          f8 EBBR protective
17 Hidden HPFS/NTF  65 Novell Netware   b8 BSDI swap        fb VMware VMFS    
18 AST SmartSleep   70 DiskSecure Mult  bb Boot Wizard hid  fc VMware VMKCORE 
1b Hidden W95 FAT3  75 PC/IX            bc Acronis FAT32 L  fd Linux raid auto
1c Hidden W95 FAT3  80 Old Minix        be Solaris boot     fe LANstep        
1e Hidden W95 FAT1  81 Minix / old Lin  bf Solaris          ff BBT            
24 NEC DOS        

[jelly]

Thanks!