[#1139] Handle Event Log Cert Issue

[iadgovuser58]

Description

When an EventLog of type EV_EFI_VARIABLE_DRIVER_CONFIG, UEFI_VARIABLE_DATA name "PK" contains a cert that isn't able to be processed, need to store that error (for print in eventlog tool, and for ACA display in ACA) but not stop validation from continuing.

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Test Instructions:

1. Run the ACA.
2. Upload support RIM which contains this particular event with a cert that isn't parsable.
3. Verify that the display still shows this event along with an error stating the non-parsable cert.
4. Run eventlogtool and verify the print still shows this event along with an error stating the non-parsable cert.

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Summary Of Changes:

1. In the UefiX509Cert class, catch the error, add the error message, and rethrow.
2. In the calling class, UefiSignatureData, catch the error and 1) store it in the toString, 2) log it in the ACA log as a warning. Then continue.
3. Cleaned up some repeated code, and incorrect cert buffer size, and comments that had gotten misaligned.

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Issues This PR Addresses:

Closes #1139