utils: include Fetch-Dependencies step in build.ps1 time tracking

[weliveindetail]

Build bot runtimes are very long and not fully transparent right now. In addition to the steps for build and test, we should keep an eye on Fetch-Dependencies.

[weliveindetail]

@swift-ci please smoke test

[weliveindetail]

Runtime reported for Fetch-Dependencies in regular CI is below 2min. PRs that evaluate build & test for Android SDKs need more tools. Download and install takes more than 5min in these cases.

Reduced log from https://ci-external.swift.org/job/swift-PR-windows/35837 shows:

T:\WiX-4.0.5.zip not found. Downloading ...
Extracting 'WiX-4.0.5.zip' ...
T:\swift-6.0.3-RELEASE-windows10.exe not found. Downloading ...
Extracting 'swift-6.0.3-RELEASE-windows10.exe' ...
T:\PythonAMD64-3.9.10.zip not found. Downloading ...
Extracting 'PythonAMD64-3.9.10.zip' ...
T:\python\packaging-24.1-py3-none-any.whl not found. Downloading ...
Installing 'packaging-24.1-py3-none-any.whl' ...
T:\android-ndk-r26b-windows.zip not found. Downloading ...
Extracting 'android-ndk-r26b-windows.zip' ...
T:\microsoft-jdk.zip not found. Downloading ...
Extracting 'microsoft-jdk.zip' ...
T:\android-cmdline-tools.zip not found. Downloading ...
Extracting 'android-cmdline-tools.zip' ...
T:\android-sdk\cmdline-tools\latest\bin\sdkmanager.bat "system-images;android-29;default;x86_64"
T:\android-sdk\cmdline-tools\latest\bin\sdkmanager.bat "platforms;android-29"
T:\android-sdk\cmdline-tools\latest\bin\sdkmanager.bat "platform-tools"
Fetch-Dependencies took 00:05:20.2656983