Didn’t Richard Nixon do that?
The problem with this is that to resign in disgrace, one must actually have a sense of shame.
We’ve had 2 presidents resign. Mary Robinson resigned in 1997 to take up a role in the United Nations. More relevant to the OP was the resignation of Cearbhall Ó Dálaigh in 1976.
In summary, the Minister for Defence referred to the president using insulting language. The Minister offered to resign but the Taoiseach refused to accept his resignation. The President then felt he had no option but to resign “to protect the dignity and independence of the presidency”.
Off the top of my head, the two situations in which I would say a person should resign in disgrace would be:
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abuse of power in a way that has identifiable negative consequences for the state (using the broad definition as in head of state) that they are representing. For example, if they used their influence to get their niece into Harvard, would be an abuse of power but not in and of itself resignation worthy. If they negotiated a trade deal that specifically to excepted their daughters company from tariffs that would count.
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Loss of confidence with their constituency such that they are no longer able to effectively provide leadership.
Trump violated part one all over the place, but may not have violated part two. Boris Johnson is more along the second tier.
Then there’s the matter that “in disgrace” is really a judgement of the Court Of Public Opinion and it refers to the whole set of circumstances and consummated events, as judged after the fact, by observers.
Stricty speaking there is no such real thing as “we call upon the governor/president/PM to resign in disgrace”, or rather if you do that you’ve just made it clear you are being partisan and obnoxious; instead you just “call upon the governor/president/PM to resign”.
(Also, BTW let’s remember that in parliamentary governments it’s normal for ministers to resign when things don’t go as desired. The example of the Irish President in '76 sounds like a reversal of the usual, but it looks like a case of “we need to replace you, but can’t fire you, so instead we’ll give you a reason to tell us to take the job and shove it and everyone keeps their pride intact.”)
I would think that the 2014 abdication of Juan Carlos, King of Spain, might qualify. Despite his historic role in the restore of democracy in Spain, his reputation had suffered severely after a series of scandals, one of them involving an alleged multi-million bribe from Saudi Arabia. He has not only abdicated but also left the country.
That reminded me of the Shah of Iran, back in the 70s.