ICU-23300 Fix static analyzer errors

[poliudian-iv]

Fix errors found by static analyzer (clangsa), when analyze chromium code. Part 5
icu4c/source/common/filteredbrk.cpp - partials can be nullptr after unsuccessful allocate memory
icu4c/source/common/loclikelysubtags.cpp - "Null pointer passed to 1st parameter expecting 'nonnull'"
icu4c/source/common/normalizer2impl.cpp - "Dereference of null pointer"
icu4c/source/common/ubidiln.cpp

• "The left expression of the compound assignment uses uninitialized memory" for insertRemove
• "Out of bound access to memory after the end of the heap area" - for runCount
• "The right operand of '+' is a garbage value" - for pLogicalStart

icu4c/source/common/ubidiwrt.cpp - all doWriteXY can return only U_BUFFER_OVERFLOW_ERROR
icu4c/source/common/ucnv.cpp - "Address of stack memory associated with local variable 'replay' is still referred to by the caller variable 'args' upon returning to the caller. This will be a dangling reference"
icu4c/source/common/ucnv2022.cpp - "Out of bound access to memory after the end of 'jpCharsetMasks'" at changeState_2022
icu4c/source/common/unames.cpp - "Out of bound access to memory after the end of 'indexes'"
icu4c/source/common/unormcmp.cpp - "Out of bound access to memory preceding 'fold2'"
icu4c/source/common/ustrcase.cpp - "Out of bound access to memory preceding 'fold2'"
icu4c/source/i18n/calendar.cpp - "The right operand of '+' is a garbage value"
icu4c/source/i18n/collationweights.cpp - "Left shift by '32' overflows the capacity of 'unsigned int'"
icu4c/source/i18n/nfrs.cpp - "Division by zero"
icu4c/source/i18n/rbt_pars.cpp - "Out of bound access to memory preceding the field 'preContext'"
icu4c/source/i18n/stsearch.cpp - "Access to field 'matchedIndex' results in a dereference of a null pointer (loaded from field 'm_search_')"
icu4c/source/i18n/tridpars.cpp - "Access to field 'valueDeleter' results in a dereference of a null pointer (loaded from variable 'hash')"
icu4c/source/common/unisetspan.cpp - "Undefined or garbage value returned to caller"

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• Required: Issue filed: ICU-23300
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Notice: the branch changed across the force-push!

• icu4c/source/common/unisetspan.cpp is now changed in the branch
• icu4c/source/i18n/stsearch.cpp is now changed in the branch
• icu4c/source/i18n/tridpars.cpp is now changed in the branch

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