How to reproduce:
1. Open the attached user's 'TestSVG.zip' project
2. Add at least two different SVG assets from 'Icons' folder to the Scene
3. Select both of icons in the Assets tab, in the Inspector window set 'Generated Asset Type' parameter to 'Textures Sprite', click Apply
4. Double click on one of SVG objects in the Scene to zoom in. You will see that one of them is merged

Expected result: Parameters are applied for each item individually by changing it in some SVG files at once
Actual result: SVG objects are merged in the Scene and Assets when applying 'Textures Sprite' parameter in some SVG assets at once

Reproducible: 2018.2.0b3, 2018.2.16f1, 2018.3.0b8, 2019.1.0a9
Not reproducible: 2018.2.0a1, 2018.2.0a8

Can't reproduce in:
- 2018.2.0b1, 2018.2.0b2 - missing Vector Graphics package
- 2018.3.0a1, 2018.3.0b1, 2019.1.0a1 - because of Package errors

Notes:
- The SVG support feature was added in Unity 2018.2.