fix(test): missing variables in test causing error in logs

[anshbansal]

This was causing exceptions in gms logs as follows

[ForkJoinPool.commonPool-worker-7] ERROR c.datahub.graphql.GraphQLController:100 - Errors while executing graphQL query: "\n            query getMetadataAnalyticsCharts($input: MetadataAnalyticsInput!) {\n                getMetadataAnalyticsCharts(input: $input) {\n                    groupId\n                    title\n                }\n            }\n        ", result: {errors=[{message=Variable 'input' has an invalid value: Variable 'input' has coerced Null value for NonNull type 'MetadataAnalyticsInput!', locations=[{line=2, column=46}], extensions={classification=ValidationError}}], data=null, extensions={tracing={version=1, startTime=2023-02-01T12:29:51.971957Z, endTime=2023-02-01T12:29:51.976488Z, duration=4550667, parsing={startOffset=1210959, duration=1064750}, validation={startOffset=2269709, duration=987709}, execution={resolvers=[]}}}}, errors: [graphql.execution.NonNullableValueCoercedAsNullException: Variable 'input' has an invalid value: Variable 'input' has coerced Null value for NonNull type 'MetadataAnalyticsInput!']

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