Update experimental incremental summary context to readonly properties

[tyler-cai-microsoft]

Make the properties on IExperimentalIncrementalSummaryContext readonly as it does not makes sense for those values to be mutable.

[github-actions]

🔗 Found some broken links! 💔

Run a link check locally to find them. See
https://github.com/microsoft/FluidFramework/wiki/Checking-for-broken-links-in-the-documentation for more information.

linkcheck output

> [email protected] ci:linkcheck /home/runner/work/FluidFramework/FluidFramework/docs
> start-server-and-test ci:start 1313 linkcheck:full

1: starting server using command "npm run ci:start"
and when url "[ 'http://127.0.0.1:1313' ]" is responding with HTTP status code 200
running tests using command "npm run linkcheck:full"


> [email protected] ci:start
> http-server ./public --port 1313 --silent


> [email protected] linkcheck:full
> npm run linkcheck:fast -- --external


> [email protected] linkcheck:fast
> linkcheck http://localhost:1313 --skip-file skipped-urls.txt --external

Crawling...

http://localhost:1313/docs/start/quick-start/
- (3412:4) 'Node.js' => https://nodejs.org/en/download (connection failed)


Stats:
  402886 links
    3134 destination URLs
       2 URLs ignored
       1 warnings
       1 errors

 ELIFECYCLE  Command failed with exit code 1.

[msfluid-bot]

⯅ @fluid-example/bundle-size-tests: +245 Bytes

Metric Name	Baseline Size	Compare Size	Size Diff
aqueduct.js	460.26 KB	460.29 KB	⯅ +35 Bytes
azureClient.js	558.25 KB	558.29 KB	⯅ +49 Bytes
connectionState.js	680 Bytes	680 Bytes	■ No change
containerRuntime.js	261.02 KB	261.04 KB	⯅ +14 Bytes
fluidFramework.js	401.41 KB	401.42 KB	⯅ +14 Bytes
loader.js	134.24 KB	134.25 KB	⯅ +14 Bytes
map.js	42.43 KB	42.44 KB	⯅ +7 Bytes
matrix.js	146.58 KB	146.58 KB	⯅ +7 Bytes
odspClient.js	525.54 KB	525.58 KB	⯅ +49 Bytes
odspDriver.js	97.85 KB	97.87 KB	⯅ +21 Bytes
odspPrefetchSnapshot.js	42.81 KB	42.82 KB	⯅ +14 Bytes
sharedString.js	163.3 KB	163.31 KB	⯅ +7 Bytes
sharedTree.js	391.87 KB	391.88 KB	⯅ +7 Bytes
Total Size	3.3 MB	3.3 MB	⯅ +245 Bytes

---

Baseline commit: 12242cf

Generated by 🚫 dangerJS against 9b642e8