Show currently selected bucket in transaction group page histogram

[jasonrhodes]

When entering the transaction detail page from the Traces overview, the histogram doesn't always show the selected bucket that the sample displayed is from. (This happens when the transaction you are visiting is not the same as the sampled transaction for that duration group in the histogram data.)

AC:

• Selected bucket is visually styled when arriving at a transaction group page with a selected transaction ID, the same as it usually is when regularly arriving at a transaction group page

See comments here for proposed solutions:

• [APM] DT design polish #24475 (comment)
• [APM] DT design polish #24475 (comment)

[elasticmachine]

Pinging @elastic/apm-ui

[alvarolobato]

The discussed solution is in this line: When we are loading the histogram we will pass the trace/transaction currently loading and make sure it is loaded from elasticsearch in the right bucket.