Update Anomaly Detector README.md to fix sample code bug

[mrbullwinkle]

Running the code as-is results in the following error:

The sample encountered an error: TypeError: Cannot read properties of undefined (reading 'daily')
    at main (C:\myapp\test4.js:31:34)
    at Object.<anonymous> (C:\myapp\test4.js:53:1)
    at Module._compile (node:internal/modules/cjs/loader:1126:14)
    at Object.Module._extensions..js (node:internal/modules/cjs/loader:1180:10)
    at Module.load (node:internal/modules/cjs/loader:1004:32)
    at Function.Module._load (node:internal/modules/cjs/loader:839:12)
    at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:81:12)
    at node:internal/main/run_main_module:17:47

Proposed change fixes this issue and results in the expected output of:

Change points were detected from the series at index:
9

Alternate solution:

Replace 2 references of TimeGranularity in line 103 and 133 with KnownTimeGranularity. Then granularity: KnownTimeGranularity.daily in line 133 will work