FINERACT-2684: Fix typo 'occured' -> 'occurred' in accounting, core and rates modules

[TianHengZhuang]

Pure typo fix in log messages and comments across fineract-accounting, fineract-core and fineract-rates modules. No behavioral change.

[adamsaghy]

@TianHengZhuang Please make sure you are using correct PR title and commit message.
Example:
FINERACT-2684: Fix typo 'occured' -> 'occurred' in accounting, core and rates modules

Also please make sure your commit is GPG signed

[TianHengZhuang]

Hi @adamsaghy, thanks for the guidance!

I've updated both the PR title and the commit message to follow the FINERACT-2684: convention. As for GPG signing, I don't currently have a GPG key configured in my environment, so the commit is unsigned. If signing is a hard requirement for this repo, please let me know and I'll see what I can do on my side.

[TianHengZhuang]

Hi @adamsaghy, an update on this: I've now configured a GPG key and re-signed the commit in this PR. The commit message follows the FINERACT-2684: convention and GitHub now shows the signature as Verified. Thanks for your patience!

[adamsaghy]

LGTM