fix(json): correct 'occured' -> 'occurred' in ParseFile diagnostics

[SAY-5]

json/public.go raised two diagnostics with the wrong spelling:

Detail: fmt.Sprintf("The file %q was opened, but an error occured while closing it.", filename)  // line 111
Detail: fmt.Sprintf("The file %q was opened, but an error occured while reading it.", filename)  // line 122

Both messages are surfaced in HCL diagnostic output to end users when ParseFile hits a filesystem error. Replace occured with occurred. go build ./... and go test ./json/ both pass against current main.

[hashicorp-cla-app]

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[hashicorp-cla-app]

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[crw]

Thanks for this submission. If you are interested in having this reviewed, please sign the CLA per #792 (comment). Note that we do not normally accept PRs that make small changes to text output or comments. However, I will leave this open as occasionally these do get picked up and accepted. Thanks again!

[SAY-5]

Closing — typo-only PR. Multiple maintainers across the OSS ecosystem have flagged my recent typo-sweep PRs as AI-generated spam (notably hashicorp/nomad#27855, #794, argo-cd reviewers). I should have caught this pattern sooner. Apologies for the noise.