fix: GraphQL throws TypeError: Cannot read property 'startToken' of undefined

[obecny]

Which problem is this PR solving?

• Fixes GraphQL throws TypeError: Cannot read property 'startToken' of undefined #271

Short description of the changes

• the graphqlTypes.Location is now always available so the param should be optional, previously it was required and it was causing the error then location was missing

[codecov]

Codecov Report

Merging #619 (980c0b9) into main (8584432) will decrease coverage by 1.51%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #619      +/-   ##
==========================================
- Coverage   96.68%   95.17%   -1.52%     
==========================================
  Files          13       25      +12     
  Lines         634     1596     +962     
  Branches      124      217      +93     
==========================================
+ Hits          613     1519     +906     
- Misses         21       77      +56     

Impacted Files	Coverage Δ
...opentelemetry-instrumentation-graphql/src/utils.ts	95.29% <100.00%> (ø)
...ages/auto-instrumentations-node/test/utils.test.ts	96.87% <0.00%> (ø)
.../opentelemetry-instrumentation-graphql/src/enum.ts	100.00% <0.00%> (ø)
...opentelemetry-instrumentation-graphql/src/types.ts	100.00% <0.00%> (ø)
...entelemetry-instrumentation-graphql/src/version.ts	100.00% <0.00%> (ø)
...nstrumentation-graphql/src/enums/AttributeNames.ts	100.00% <0.00%> (ø)
...try-instrumentation-graphql/src/instrumentation.ts	92.72% <0.00%> (ø)
...tapackages/auto-instrumentations-node/src/utils.ts	96.77% <0.00%> (ø)
...entelemetry-instrumentation-graphql/test/helper.ts	100.00% <0.00%> (ø)
...entelemetry-instrumentation-graphql/src/symbols.ts	100.00% <0.00%> (ø)
... and 3 more