Fix some cases of `std::vector::push_back` in the rvs mode

[gojakuch]

Fixes: #1071

[github-actions[bot]]

clang-tidy review says "All clean, LGTM! :+1:"

[codecov[bot]]

Codecov Report

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

Project coverage is 94.24%. Comparing base (2e5560e) to head (71ca82a). Report is 1 commits behind head on master.

Additional details and impacted files

[](https://app.codecov.io/gh/vgvassilev/clad/pull/1103?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Vassil+Vassilev) ```diff @@ Coverage Diff @@ ## master #1103 +/- ## ======================================= Coverage 94.24% 94.24% ======================================= Files 55 55 Lines 8447 8447 ======================================= Hits 7961 7961 Misses 486 486 ```

[github-actions[bot]]

clang-tidy review says "All clean, LGTM! :+1:"

[gojakuch]

@vgvassilev the clang-tidy-review check fails because of some docker issue

UPD: all good now, I just reran it and it worked. can we merge?

[github-actions[bot]]

clang-tidy review says "All clean, LGTM! :+1:"