Fix SDK version parsing from global.json in install script on macOS

[kondratyev-nv]

Running install script scripts/obtain/dotnet-install.sh with jsonfile argument works on macOS only when sdk section has a single property version. When sdk section has multiple properties, for example,

"sdk": {
    "version":  "5.0.100-preview.6.20310.4",
    "allowPrerelease": true,
    "rollForward": "major"
  }

a version is detected as 5.0.100-preview.6.20310.4allowPrerelease:truerollForward:major.
Also, in a case when version is not the first property in sdk a version can not be detected returning an error dotnet_install: Error: Unable to find the SDK:version node in `global.json` .

The problem seems to be in line:

sdk_list="$(echo -e "${sdk_list}" | tr -d '[[:space:]]')"

On macOS, echo does not have a -e argument, and all lines of key-value pairs in sdk_list are merged into a single line. So, removing it seems to fix it. I don't have a Linux to test the changes, but I hope CI will catch any issues on Linux.

[dnfadmin]

All CLA requirements met.

[marcpopMSFT]

@donJoseLuis does the install script change needed in the install-scripts repo and should we remove the copy from this repo to reduce confusion?

[marcpopMSFT]

Ping @donJoseLuis

[kondratyev-nv]

@marcpopMSFT Thanks for the help! I've created an issue in install-scripts repo dotnet/install-scripts#61 concerning that problem. Unfortunately, I wan not able to create a similar PR in install-scripts repo, so I'll wait for a response to the issue.

[marcpopMSFT]

@bozturkMSFT Should he close this and do all of the work in the install-scripts repo?