Something error when the version of tag/edge schema is greater than 256

[sworduo]

If the version of schema is greater than 256, let's say 500, then 'desc tag xxx' would only return the schema with version 255 but not the largest one. All the alter operations including 'alter tag/edge xxx add/drop/change' would have the same problem in v2.0.0. #3889 (comment)

(root@nebula) [schema_space]> alter tag tag_1 add (abcde string)
Execution succeeded (time spent 3135/3574 us)

Wed, 09 Mar 2022 14:44:05 CST

(root@nebula) [schema_space]> alter tag tag_1 drop (abcde)
[ERROR (-8)]: Not existed!

Wed, 09 Mar 2022 14:44:13 CST

Furthermore, in v2.0.0, when the version of shema is 255, the latest alter operation will based on 255 instead of 256 or higher. When I execute

(root@nebula) [schema_space]> alter tag tag_1 add (abcde string)
Execution succeeded (time spent 2741/3092 us)

Wed, 09 Mar 2022 15:14:55 CST

(root@nebula) [schema_space]> alter tag tag_1 add (abcd1e string)
Execution succeeded (time spent 3675/4125 us)

Wed, 09 Mar 2022 15:16:03 CST

(root@nebula) [schema_space]> alter tag tag_1 add (abcd12e string)
Execution succeeded (time spent 3381/3771 us)

Wed, 09 Mar 2022 15:16:05 CST

(root@nebula) [schema_space]> alter tag tag_1 add (abcd123e string)
Execution succeeded (time spent 2668/2999 us)

Wed, 09 Mar 2022 15:16:07 CST

(root@nebula) [schema_space]> alter tag tag_1 add (abcd1234e string)
Execution succeeded (time spent 3078/3454 us)

Wed, 09 Mar 2022 15:16:10 CST

The log is

I0309 15:14:14.469921 25032 AlterTagProcessor.cpp:101] Alter Tag tag_1, tagId 531 , new version: 256
I0309 15:14:53.660425 25032 AlterTagProcessor.cpp:101] Alter Tag tag_1, tagId 531 , new version: 256
I0309 15:14:54.676265 25032 AlterTagProcessor.cpp:101] Alter Tag tag_1, tagId 531 , new version: 256
I0309 15:14:55.574775 25032 AlterTagProcessor.cpp:101] Alter Tag tag_1, tagId 531 , new version: 256
I0309 15:16:03.607669 25032 AlterTagProcessor.cpp:101] Alter Tag tag_1, tagId 531 , new version: 256
I0309 15:16:05.817402 25032 AlterTagProcessor.cpp:101] Alter Tag tag_1, tagId 531 , new version: 256
I0309 15:16:07.951567 25031 AlterTagProcessor.cpp:101] Alter Tag tag_1, tagId 531 , new version: 256
I0309 15:16:10.092022 25031 AlterTagProcessor.cpp:101] Alter Tag tag_1, tagId 531 , new version: 256