Improve the rounding off logic in Balance class

[aniketsingh03]

Changes

• This PR improves the logic in misc.go for improved rounding off when converting floats to ints

Fixes

• flakiness in bl-update #752

Tests

Tasks to complete before merging PR:

• Ensure system tests are passing. If not Run them manually to check for any regressions 📋
• Do any new system tests need added to test this change? do any existing system tests need updated? If so create a PR at 0chain/system_test
• Merge your system tests PR to master AFTER merging this PR

Associated PRs (Link as appropriate):

• blobber:
• 0chain:
• system_test:
• zboxcli: Improve the rounding off logic in Balance class (for changes in https://github.com/0chain/gosdk/pull/794) zboxcli#360
• zwalletcli: Changes conforming to https://github.com/0chain/gosdk/pull/794 zwalletcli#211
• Other: ...

[dabasov]

lgtm

[service-0chain]

Manual system tests [failure] with the following config

config	value
tests skipped	FALSE
system-tests	master
gosdk	fix-rounding-off-for-balance
zboxcli	fix-rounding-off-for-balance
zwalletcli	fix-rounding-off-for-balance
0chain	staging
blobber	staging
authorizer	staging
0box	staging
0block	staging
0dns	staging
explorer	staging
0proxy	staging
0search	staging

[peterlimg]

LGTM

[cnlangzi]

LGTM

[service-0chain]

Manual system tests [success] with the following config

config	value
tests skipped	TRUE
system-tests	master
gosdk	fix-rounding-off-for-balance
zboxcli	staging
zwalletcli	staging
0chain	staging
blobber	staging
authorizer	staging
0box	staging
0block	staging
0dns	staging
explorer	staging
0proxy	staging
0search	staging