Yes,
open an ebook with the issue in the Calibre editor. Select title row, right click, Edit.
Double click on an HTML file, not near the start. You'll have a preview in the right window and see the HTML in the middle window.
Click on the start of a paragraph in the preview.
See the HTML in the middle window starting with <, it has a Class.
Quote:
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<p class="calibre9">And poor, peevish Mrs. Coventry sank into an easy chair with a nervous sigh and the air of a martyr, while her pretty daughter hovered about her with affectionate solicitude.</p>
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Double click on stylesheet.css (or similar).
Scroll down to find the matching class, which is prefixed with a dot, like .calibre9 in the example, but it could be msonormal1 or anything.
Then you can edit or add to the css.
There is plenty of css help on here
https://www.w3schools.com/CSSref/pr_dim_line-height.asp
Note that if a setting is missing, then either the ereader (or App) default is used, or an enclosing scope sets it, or the user can change it if it's a GUI item.
The line height should not normally be set anywhere in ebook CSS so that the User GUI linespacing will work.
Also this means if using a docx from Word or LO Writer, the line spacing shouldn't be set except for maybe special cases, not at all in most styles.