Global picture indicator 'Net ODA provided by non-DAC donors, % of GNI' decimal places

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Check one of the following options with "x" and add the appropriate label to the issue as well

[X] Bug report 

[ ] Regression (behaviour that used to work and stopped working in a new release)

**Describe the Issue**
Indicator: Net ODA provided by non-DAC donors, % of GNI on the Global picture. Which is driven by the data series fact.ssc_percent_gni should be shown on the front-end to two decimal places. Unsure @edwinmp whether this is both a front-end fix alone, or needs a database update as well.

**To Reproduce**
Replace the content below with the steps to reproduce the behaviour.
1. Go to 'Global picture'
2. Click on 'Net ODA provided by non-DAC donors, % of GNI'

**Expected Behaviour**
Legend and hover over tool tip should show to two decimal places as opposed to one. Exactly as done on the visual for 'Net ODA provided by DAC members, % of GNI'.

**Additional Context**
The reason this is flagged is the ODA%GNI estimates are typically expressed to 2 decimal places, where the individual second decimal can make a difference to the figure quoted, for example the front-end on the data hub shows Turkey to be 0% in 2002, when it in-fact is 0.04%, which has been rounded down with the one decimal place available on data hub.

Requested Delivery Date: low priority