Extend collection of Unicode combining characters to beyond the BMP
The former limit was perhaps a carryover from an older hand-coded
table. Since commit
bab982161 we have enough space in mbinterval to
store larger codepoints, so collect all combining characters.
Discussion: https://www.postgresql.org/message-id/
49ad1fa0-174e-c901-b14c-
c484b60907f1%40enterprisedb.com