SSIS DevOps Tools Build SSIS task version 1.* fails ##[error] System.Xml.XmlException

Question

I am trying to update from the SSIS DevOps Tools Build SSIS task version 0.* to 1.*.

My build which works in version 0.* and locally in Visual Studio . It fails when using version 1.* of the Build SSIS task on the windows-2019 Agent, I have tried other agents but still get the same error.

the error is

##[error]12/02/2021 19:56:11 System.Xml.XmlException: An error occurred while parsing EntityName. Line 1, position 146.
   at System.Xml.XmlTextReaderImpl.Throw(Exception e)
   at System.Xml.XmlTextReaderImpl.ParseEntityName()
   at System.Xml.XmlTextReaderImpl.ParseEntityReference()
   at System.Xml.XmlTextReaderImpl.Read()

...

the error occurs after (names change to protect the innocent :-))

12/02/2021 19:56:06 Build started: SQL Server Integration Services project: Full ...
12/02/2021 19:56:06 Starting project consistency check ...
12/02/2021 19:56:07 Project consistency check completed. The project is consistent.
12/02/2021 19:56:07 File 'D:\a\1\s\DP\obj\Development\myproject.dtproj' get updated.
....(all of the project objects are retrieved)
12/02/2021 19:56:09 File 'D:\a\1\s\DP\obj\Development\hstg_package1.dtsx' get updated.
12/02/2021 19:56:09 File 'D:\a\1\s\DP\obj\Development\BATCH_package1.dtsx' get updated.
12/02/2021 19:56:10 Applied active configuration to 'Project.params'.
12/02/2021 19:56:10 Applied active configuration to 'cfg_remove_error.dtsx'.
12/02/2021 19:56:10 Applied active configuration to 'cfg_SEND_EMAILS.dtsx'.
12/02/2021 19:56:10 Applied active configuration to 'ALA-ExecuteLogicApp1.dtsx'.
##[error]12/02/2021 19:56:11 System.Xml.XmlException: An error occurred while parsing EntityName. Line 1, position 146.

any help advice appreciated. thanks