.Net: Fix bash script to build the dotnet solution (#10003)

### Motivation and Context

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Small fix for the `build.sh` bash in the dotnet folder to locally build
and test the solution. It was not working as the script was already in
the `dotnet` folder

### Description

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These notes will help understanding how your code works. Thanks! -->

Provide another way to navigate to the dotnet folder before triggering
`dotnet build & dotnet test` commands.

### Contribution Checklist

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- [x] The code builds clean without any errors or warnings
- [x] The PR follows the [SK Contribution
Guidelines](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md)
and the [pre-submission formatting
script](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md#development-scripts)
raises no violations
- [x] All unit tests pass, and I have added new tests where possible
- [x] I didn't break anyone 😄

Co-authored-by: Chris <[email protected]>

dotnet/build.sh

@@ -2,12 +2,12 @@
 
 set -e
 
-HERE="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)/"
-cd "$HERE"
+SCRIPT_DIR=$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )
 
-cd dotnet
+pushd "$SCRIPT_DIR" > /dev/null
 
 # Release config triggers also "dotnet format"
 dotnet build --configuration Release --interactive
-
 dotnet test --configuration Release --no-build --no-restore --interactive
+
+popd > /dev/null