fix(types): Fix incorrect sampled type on Transaction

[quisido]

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@sentry/types does not align with @sentry/core, and it causes build errors when exactOptionalPropertyTypes is true.

Example error below:

.../Yarn/Berry/cache/@sentry-core-npm-7.107.0-d7aa1d2661-10c0.zip/node_modules/@sentry/core/types/tracing/transaction.d.ts:5:22 - error TS2420: Class 'import(".../Yarn/Berry/cache/@sentry-core-npm-7.107.0-d7aa1d2661-10c0.zip/node_modules/@sentry/core/types/tracing/transaction").Transaction' incorrectly implements interface 'import(".../Yarn/Berry/cache/@sentry-types-npm-7.107.0-a994f84978-10c0.zip/node_modules/@sentry/types/types/transaction").Transaction'.
  Types of property 'sampled' are incompatible.
    Type 'boolean | undefined' is not assignable to type 'boolean'.
      Type 'undefined' is not assignable to type 'boolean'.

5 export declare class Transaction extends SpanClass implements TransactionInterface {
                       ~~~~~~~~~~~


Found 1 error in .../Yarn/Berry/cache/@sentry-core-npm-7.107.0-d7aa1d2661-10c0.zip/node_modules/@sentry/core/types/tracing/transaction.d.ts:5

This change fixes this.

[Lms24]

Thank you!

[AbhiPrasad]

Released with https://github.com/getsentry/sentry-javascript/releases/tag/7.108.0