fix bug in example golang code in graphql.filters.bm25

[cryo-zd]

What's being changed:

The example golang code for keyword searching could not run properly, we fix some syntax error so that it could work.

The error message of the original code is as follows：
./main.go:30:12: invalid composite literal type string
./main.go:31:3: label properties defined and not used
./main.go:31:15: non-name []string{…} on left side of :=
./main.go:32:11: assignment mismatch: 2 variables but client.GraphQL().Bm25ArgBuilder().WithQuery(query).WithProperties returns 1 value
./main.go:34:20: undefined: properties
./main.go:41:5: client.GraphQL().Get().WithClassName(className).WithFields(title, _additional).WithBm25 undefined (type *graphql.GetBuilder has no field or method WithBm25, but does have method WithBM25)

Type of change:

• Documentation updates (non-breaking change to fix/update documentation)
• Website updates (non-breaking change to update main page, company pages, pricing, etc)
• Content updates – blog, podcast (non-breaking change to add/update content)
• Bug fix (non-breaking change to fixes an issue with the site)
• Feature or enhancements (non-breaking change to add functionality)

How Has This Been Tested?

• GitHub action – automated build completed without errors
• Local build - the site works as expected when running yarn start

note, you can run yarn verify-links to test site links locally

[orca-security-eu]

Orca Security Scan Summary

Status	Check	Issues by priority
Passed	Infrastructure as Code	0   0   0   0	View in Orca
Passed	SAST	0   0   0   0	View in Orca
Passed	Secrets	0   0   0   0	View in Orca
Passed	Vulnerabilities	0   0   0   0	View in Orca

[weaviate-git-bot]

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[cryo-zd]

I agree with the CLA.

[g-despot]

Thank you for the contribution 😄