Next dev iteration

[0xnm]

What does this PR do?

Bumping dev version to 1.15.0 because of 1.14.0 release.

Review checklist (to be filled by reviewers)

• [ ] Feature or bugfix MUST have appropriate tests (unit, integration, e2e)
• [ ] Make sure you discussed the feature or bugfix with the maintaining team in an Issue
• [ ] Make sure each commit and the PR mention the Issue number (cf the CONTRIBUTING doc)

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 78.27%. Comparing base (46233f7) to head (ef513cd).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## develop #267 +/- ## ============================================= - Coverage 78.34% 78.27% -0.07% + Complexity 254 253 -1 ============================================= Files 31 31 Lines 914 911 -3 Branches 114 114 ============================================= - Hits 716 713 -3 Misses 147 147 Partials 51 51 ``` [see 2 files with indirect coverage changes](https://app.codecov.io/gh/DataDog/dd-sdk-android-gradle-plugin/pull/267/indirect-changes?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=DataDog)